After Saddam Hussein’s ouster in 2003, Iraq’s new leaders struggled to chart a democratic course after decades of dictatorship. Two events were pivotal. First, the U.S. decision to bar the long-ruling Baath Party—and the way it was implemented—created a political vacuum. Second, disbanding the military—alienating hundreds of thousands of trained men with no alternative—left a security void. Iraq suffered through a civil war, political turmoil, widespread corruption, sectarian tensions and an extremist insurgency that seized a third of the country. Iraq has evolved through four rocky phases.

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The first phase, the initial transition between 2003 and 2007, started with a U.S.-led Coalition Provisional Authority. Each ministry had a U.S. advisor. As a self-declared occupying force, the U.S. military was responsible for national security, but at least 100,000 people died during its eight-year intervention (some estimates were as high as half a million). The transition included building new parties, recruiting and training new military forces, creating nascent civil society, and drafting new laws. In 2005, Iraqis voted on a new constitution, which introduced individual rights, including for religious and ethnic minorities.

The political balance of power—dominated for centuries by Sunnis—shifted dramatically. For the first time, the Shia majority claimed the prime minister’s slot and had sufficient leverage to control key ministries and other levers of the state. For the first time, Iraq also had a Kurdish president. Kurds, who had long demanded autonomy from Baghdad, became part of the state; the constitution recognized autonomy for the Kurdistan Regional Government (KRG) and formal status of its Peshmerga forces. Sunnis, who had dominated the state under Saddam, maintained the key position of parliamentary speaker but lost many other powers.

The transition also witnessed the outbreak of sectarian tensions, symbolized by the bombing of the al-Askari shrine, a Shia holy site, in early 2006. The blast destroyed the famous gold dome and triggered violence across Iraq for years. The tensions were exploited by Abu Musab al-Zarqawi, a Jordanian jihadi who had fought in Afghanistan and moved to Iraq to lead al-Qaida in Iraq. He was linked to bombings, kidnappings and beheadings. He was the first in a series of jihadi leaders determined to foment hostilities among Iraq’s ethnic and religious communities. Al-Zarqawi was killed in a U.S. airstrike in mid-2006. The group subsequently rebranded as the Islamic State in Iraq (ISI).

The second phase, from 2007 to 2011, was marked by the U.S. military surge of an additional 30,000 troops—adding to 130,000 already deployed—to help stem the escalating bloodshed. The surge overlapped with the so-called “Awakening” among Iraq’s Sunni tribes. They turned against the jihadi movement and started working with U.S. troops. The collaboration initially contained ISI. By 2011, the United States opted to withdraw from Iraq, with an understanding from the Baghdad government that it would incorporate the Sunni tribes into the Iraqi security forces to contain the sectarian divide.

The third phase played out between 2012 and 2017, as the government of Iraq did not follow through on promises to employ and pay the minority Sunnis who had fought the jihadis. Thousands of Sunnis were detained. By early 2013, tens of thousands of Sunnis participated in anti-government protests in Ramadi, Fallujah, Samarra, Mosul and Kirkuk. The Sunnis accused then Iraqi Prime Minister Nuri al-Maliki of exclusionary sectarian policies. Maliki’s relationship with the Kurds also deteriorated.

The Shia-dominated government’s failure to follow through with the Sunnis allowed ISI to reconstitute. The underground extremist movement recruited thousands of Sunnis, including beyond Iraq’s borders. In 2013, it expanded into Syria and rebranded again as the Islamic State in Iraq and Syria (ISIS). Its militia captured Fallujah in December 2013. Despite having far more numbers, the Iraqi army crumbled. By June 2014, ISIS took control of a third of the country. ISIS leader Abu Bakr al-Baghdadi declared the creation of an Islamic State in Mosul, Iraq’s second largest city, and named himself caliph. It instituted a reign of terror that included rape, abductions, executions, mass murder, pillaging, extortion, seizure of state resources, and smuggling.

The rise of ISIS further split Iraqi society. Grand Ayatollah Ali al-Sistani, the Shia world’s top marja, responded to the Sunni jihadis movement with a fatwa calling Iraqis to take up to arms. Tens of thousands of men, mostly Shia, joined new and old militias, many supported by Iran. More than 60 armed groups eventually merged under the umbrella of the Popular Mobilization Forces (PMF).

The rise of ISIS also led to foreign intervention a second time. Iran was the first to provide military assistance, partly because Sunni jihadis came within 25 miles of its border. In September 2014, the United States formed “The Global Coalition to Defeat ISIS,” made up of 79 countries and institutions, including NATO, the European Union, and the Arab League. The Obama administration re-deployed U.S. troops to retrain and advise the Iraqi Army; it also launched airstrikes that continued for more than three years until the Islamic State collapsed. Turkey deployed its own troops in northern Iraq to help protect Sunnis and Turkmen, but also to contain the influence of the Kurdistan Workers’ Party (PKK) that operated in both Iraq and Turkey.

Between 2015 and 2017, Iraqi security forces, Kurdish Peshmerga forces and the PMF—backed by airpower provided by the U.S.-led coalition—gradually retook territory from ISIS. Tens of thousands of jihadis reportedly were killed. In December 2017, Prime Minister Haider al-Abadi declared victory.

A fourth phase began in 2018 after the government regained control over all Iraqi territory. In May 2018, a national election redesigned the political landscape. Shia cleric Moqtada al-Sadr led an unlikely coalition with secular Sunnis and communists that won the largest number of seats while an Iran-backed block came second. Parliament elected veteran Kurdish politician Barham Salih as president and Muhammad al-Halbusi, a 37-year-old Sunni lawmaker, as speaker. Salih designated Adil Abdul al-Mahdi, a 76-year-old economist and veteran Shia politician to be prime minister. Although both have long been desired by Iraqis and international interlocutors to lead in those positions, they were unable to usher the changes in governance and reform that Iraq needed. In October 2019, hundreds of thousands of protestors took to the street to demand change and reform. However, the response from government forces and armed groups was lethal, leaving over 20,000 people injured and more than 450 people killed.

Iraq’s turbulent transition reflected the wider changes and challenges across the Middle East in the 21st century:

  • The biggest threat is not conventional warfare but asymmetrical conflict launched by militias and non-state actors. Despite losing its territory in 2017, ISIS remnants continued to attack civilian and military targets in Iraq. Jihadism remained a threat to several Arab governments by playing on Sunni grievances still not addressed by governments.
  • Instability made Iraq vulnerable to regional and international rivalries. The U.S.-led invasion and occupation triggered deeper intervention by Iran. Tehran successfully applied its “Hezbollah” model in Iraq by supporting Shia armed groups, some of which began participating in Iraqi politics. Some groups—such as Harakat Hezbollah al-Nujaba, the Imam Ali Brigades and Asaib Ahl al-Haq—also became useful in Iran’s campaign to save the government of President Bashar al-Assad in neighboring Syria. In late 2019 and early 2020, rising tensions between the United States and Iran played out in Iraq. Armed group members and affiliates of Iran stormed the external perimeter of the U.S. Embassy, and the United States killed Iranian General Qassem Soleimani and Iraqi PMF leader Abu Mahdi al-Muhandis in a drone strike.
  • For all its turbulence, Iraq’s transition produced some positive changes. Iraq reintegrated into regional and international forums. The number of media outlets increased dramatically. The long-repressed citizenry became politically active. Inspired partly by the 2011 Arab uprisings, Iraqis demonstrated to demand jobs and basic services. They also called out officials for corruption. Even amid the fight against ISIS in 2015 and in subsequent years, Iraqis pressured the government for reforms. One message from the 2018 election and recurring demonstrations was that many Iraqis wanted to limit outside influence by Iran, Turkey and others. In 2018, Iraq produced oil at record levels. The economic wellbeing of many Iraqis improved, although unemployment and poverty were still serious problems.

Originally posted February 2019. Updated May 2020.

This timeline was assembled with the help of graphic research by Lindsay Jodoin and editorial research by Garrett Nada, Lindsay Jodoin, Eli Pollock, Grace Makhoul, and Yomnna Helmi.


March 19

After months of diplomatic attempts to engage President Saddam Hussein failed, President Bush launched Operation Iraqi Freedom. It began with massive air strikes described as “shock and awe.” On May 1, Bush delivered his “Mission Accomplished” speech aboard the USS Lincoln, prematurely declaring the end of major combat in Iraq.

May 12

U.S. Ambassador Paul Bremer was appointed to lead the Coalition Provisional Authority (CPA), the U.S.-led ruling authority during the transition. On May 16, CPA Administrator Bremer outlawed the former ruling Baath Party and ordered Iraq institutions to “de-Baathify,” which removed Baath Party members from public sector jobs and ministerial posts. On May 23,Bremer dissolved the Iraqi military, leaving more than 350,000 soldiers without jobs. Former soldiers with the rank of colonel or above were banned from working for the new Iraqi government and did not receive severance or retirement. “We could have done a lot better job of sorting through that and keeping the Iraqi army together,” General Ray Odierno, the U.S. Army chief of staff, told TIME in 2015. “We struggled for years to try to put it back together again.” Some of the disaffected Sunni men later joined militant groups, including ISIS. Bremer served as head of a caretaker government until the 2004 handover to a provisional Iraqi government.

August 19

A bombing at the U.N. headquarters in Baghdad killed 23 people, including U.N. envoy Sergio Vieira de Mello, and triggered the withdrawal of hundreds of U.N. workers from Iraq. Jordanian-born jihadi Abu Musab al-Zarqawi—who led a group originally known as Tawhid and Jihad and later as al-Qaida of Iraq—was responsible. On August 29, a car bomb killed 95 people at Najaf’s Imam Ali Mosque, the holiest Shia shrine in Iraq. Among the dead was Ayatollah Muhammad Bakr al-Hakim, an important religious leader who had cooperated with U.S. forces. In October and November, Iraqi insurgents launched a massive offensive during the month of Ramadan that struck dozens of targets, including the Red Cross headquarters in Baghdad.

December 13

U.S. forces captured Saddam Hussein in a hole on a farm near his hometown of Tikrit. Hussein had been broadcasting pro-insurgency messages since the U.S. invasion, and had evaded several U.S. attempts to kill or capture him. U.S. troops had killed Saddam Hussein’s sons, Uday and Qusay, in a gun battle at their Mosul hideout on July 22.


January 30

National Security Adviser Condoleezza Rice admitted for the first time the United States had been mistaken about Saddam Hussein’s possession of weapons of mass destruction (WMD), the main pretext for the war. The admission followed the January 23 testimony and resignation of David Kay, the chief weapons inspector of the U.S.-run Iraq Survey Group that had been tasked with finding Iraq’s WMD. He said that the intelligence assessments of Iraq’s weapons program before the war had been almost entirely incorrect.

February 1

Dual suicide bombings targeted the Kurdistan Democratic Party (KDP) and Patriotic Union of Kurdistan (PUK) party offices in Iraqi Kurdistan, killing at least 70, including the deputy prime minister of the Kurdistan Regional Government. U.S. forces suspected al-Qaida or Ansar al-Islam, a Kurdish Islamist group. On March 2,terrorists attacked Shia worshippers observing the Ashura holiday in Baghdad and Karbala with small arms and explosives. At least 140 were killed in the deadliest day since the U.S. occupation began. Coalition forces suspected al-Zarqawi. On May 17, Zarqawi’s group assassinated Ezzedine Salim, the head of the Iraqi Governing Council.

April 4

The U.S. military launched the unsuccessful First Battle of Fallujah to take control of the city from Sunni insurgents. The Mahdi Army, a Shia militia led by cleric Moqtada al-Sadr, conducted its first attacks on coalition forces in Amara, Baghdad, Kufa, and Najaf. In April and May, chronic prisoner abuse by U.S. forces in the Abu Ghraib Prison outside of Baghdad was revealed in graphic photographs and prisoner testimonials. The scandal triggered backlash against the United States and U.S. forces.

June 28

The CPA and Iraqi Governing Council handed over political control of the country to the Iraqi Interim Government under Interim Prime Minister Iyad Allawi, a Shia. The move transferred nominal sovereignty from U.S. to Iraqi hands, although the government had limited powers.


Al-Zarqawi’s group formally declared allegiance to Osama bin Laden and became known as al-Qaida in Iraq (AQI). The group had perpetrated about a dozen attacks in Iraq. It was also infamous for beheading foreign hostages. In November and December, U.S. forces conducted Operation Phantom Fury, or the Second Battle of Fallujah, to take control of Fallujah from AQI and other Sunni insurgent groups. The operation was the bloodiest yet for U.S. forces in Iraq, but it succeeded.


January 30

Iraqis voted for the Transitional National Assembly in the first elections since the U.S. invasion. Shia cleric Ayatollah al-Sistani endorsed the elections and encouraged participation. The United Iraqi Alliance, a Shia Islamist coalition, secured 47 percent of the vote. Kurdish parties secured approximately 25 percent. And Prime Minister Allawi’s party came in third. Violence and low Sunni turnout marred the outcome of the first elections.

February 28

At least 122 people were killed in Hilla, south of Baghdad, in the deadliest single bombing since the U.S. invasion. In April and May, the Sunni insurgency, increasingly dominated by AQI, escalated its bombing campaign. Insurgents killed hundreds of Shias to undermine the government and trigger a wider sectarian conflict. Shia leaders urged their followers not to take revenge. Iraq suffered 135 car bombings in April, up from 69 in March.

April 6-7

Iraq’s parliament installed Jalal Talabani, a Kurdish leader, as president of Iraq. President Talabani named Ibrahim Jaafari, from a religious party, as prime minister. On June 14, Massoud Barzani was sworn in as president of the Kurdistan Region of Iraq, the result of an agreement with Iraqi President Talabani on power sharing between their rival Kurdish parties.

July through December

U.S. and Iraqi forces conducted Operation Sayaid, a series of operations to undermine the Sunni insurgency and retake Anbar province. On August 31, fears of a suicide bomber approaching triggered a panicked stampede by Shia pilgrims on a bridge to the Kadhimiyah Shrine, in northern Baghdad, which killed more than 95 people. On September 14, AQI killed at least 150 people in a series of attacks on Baghdad’s Shia population. In a video, al-Zarqawi declared war on all Iraq’s Shias.

November 13

U.S. troops discovered 173 starved and tortured bodies in the cells of an Interior Ministry detention center. All the detainees were Sunnis.

November 19

Twin suicide bombings at two Shia mosques in Khanaqin, near the eastern border with Iran, killed 90 Iraqi civilians. The bombings occurred as U.S. and Iraqi forces engaged in heavy fighting in Anbar province as part of Operation Steel Curtain, the latest in a series of Anbar province operations targeting the Sunni insurgency. In November, the United States conducted 120 airstrikes in Iraq, up from 25 in January.

December 15

Following the vote to ratify a new constitution in October, Iraqis elected a new parliament for the first time since the U.S. invasion. Turnout was high. The results were announced in January. The United Iraqi Alliance—a list of Islamist groups—won the most seats, 128, but fell 10 short of the majority needed to govern without a coalition. The secular list of former Prime Minister Allawi won just 25 seats. The two Sunni lists collectively won 55 seats, significantly increasing their representation compared to the previous parliament. Sunnis had largely boycotted the January 2005 election.


January 5

In separate attacks AQI suicide bombers attacked police recruits in Ramadi and pilgrims in Karbala, killing more than 140 people. On January 15, AQI merged with other Sunni insurgent groups and was briefly renamed the Mujahideen Shura Council. It was still commonly referred to as AQI.

February 13

The United Iraqi Alliance, which won the December parliamentary elections, selected Ibrahim Jaafari as prime minister, the second since Saddam’s ouster. In March, Kurdish and Sunni parties rejected Jaafari as prime minister and refused to join a national unity government because he had failed to stop escalating sectarian violence. U.S. Ambassador Zalmay Khalilzad told Shia leaders that President Bush opposed Jaafari too.On April 21, Jaafari agreed to step aside.

February 16

After 22 policemen were arrested for killing Sunnis, the Interior Ministry launched an investigation into its personnel who had allegedly ran death squads. The arrests brought attention to a pattern of extrajudicial killing by Iraqi forces targeting minority Sunnis. On February 22, the famous golden dome of the al Askari Shrine in Samarra, one of the holiest Shia shrines, was destroyed in a bombing widely blamed on Sunni jihadis of AQI. The shrine bombing triggered violence by Shia and Sunni militias that killed more than a 1,000 people. Shia leaders al-Sadr and Grand Ayatollah al-Sistani called for calm, but Shia militias, including al-Sadr’s own Mahdi Army, reportedly continued sectarian killings. On March 26, U.S. Ambassador Khalizad charged that violence by Shia militias exceeded killings by Sunni terrorists or insurgents. He urged the prime minister to reign in militias and end extrajudicial killings by people with links to the government. On April 7, a triple suicide bombing at the Shia Buratha mosque in Baghdad killed 85 and wounded 160. The attack came amid a post-election political crisis and related sectarian violence.

May 21

The Iraqi Parliament approved Nuri al-Maliki as Iraq’s third prime minister since Saddam Hussein’s ouster. His cabinet included representatives from most Iraqi sects and ethnic groups, although three key cabinet positions remained unfilled due to sectarian disagreements. On June 8, Parliament approved Maliki’s appointees. General Abdul-Qader Mohammed Jassim al-Mifarji, a Sunni, became defense minister. Jawad al-Bolani, a Shia, became interior minister. Sherwan al-Waili, a Shia, became national security minister.

June 7

Al-Zarqawi, the AQI leader linked to bombings, kidnappings and beheadings, was killed in a U.S. air strike. He was succeeded by Abu Ayyub al-Masri. On June 14, Prime Minister Nuri al Maliki released his security plan, Operation Together Forward, to improve conditions in the Baghdad area amid increasing sectarian bloodletting. It introduced curfews, checkpoints, and joint Iraqi-U.S. raids on insurgent cells. On June 25, Prime Minister Maliki delivered his 24-point plan to restore order and reduce sectarian violence in Iraq. The reconciliation plan promised amnesty for those imprisoned on charges unrelated to crime, war crimes, and crimes against humanity. Videos of three Russian diplomats kidnapped on June 3 being executed was released online. On July 1, at least 66 people were killed in a car bombing at an outdoor market in the Shia Sadr City area of Baghdad.

July 9

Mahdi Army militiamen killed at least 40 Sunnis during house searches and at phony checkpoints in Baghdad. Some two-dozen people were killed in a double car bombing at a mosque in Baghdad’s Kasra district. On July 11, a double suicide bombing near the entrance to the Green Zone killed more than 50 people. The Mujahideen Shura Council, an umbrella Sunni Islamist group that included AQI, claimed responsibility. Prime Minister Maliki rejected suggestions that Iraq was falling into civil war despite deepening violence. On July 17, a shooting and mortar attack in Mahmoudiyah, a predominantly Shia city, killed at least 40 people. The attack marked several days of intensifying violence in retaliation for the July 9 Mahdi Army killings.July was the deadliest month for civilians since violence erupted, according to the Iraqi Health Ministry. Nearly 3,500 Iraqis—or an average of 110 Iraqis per day—were killed that month, although the United Nations said the body count was higher. More than half of the deaths occurred in the Baghdad area. The United States increased troop deployments on an emergency basis, despite hopes earlier in the year for a partial withdrawal.

October 15

Masri disbanded the Mujahideen Shura Council, which included AQI, and announced the establishment of the Islamic State in Iraq (ISI). Masri and Abu Omar al-Baghdadi, another al-Zarqawi successor, led the new group. On October 20, the U.S. military announced that the Baghdad security plan, Operation Together Forward, had not stemmed violence in the capital.On November 23, bombs in Sadr City, a Shia enclave of Baghdad, killed 215 Shias. In an act of revenge, Shia militiamen burned six Sunnis alive after they left Friday prayers.

November 5

An Iraqi special tribunal sentenced Saddam Hussein to death for the 1982 killing of 148 Shias in the town of Dujail. On December 30, Hussein was executed by hanging for crimes against humanity. “Justice, in the name of the people, has carried out the death sentence against the criminal Saddam, who faced his fate like all tyrants, frightened and terrified during a hard day which he did not expect,” Prime Minister Maliki said in a statement.


January 10

President Bush announced the “surge” of an additional 30,000 U.S. troops to stop mass sectarian violence, counter jihadi extremism and stabilize the country. The parallel was to give Iraqi leaders time and space to forge political reconciliation. Between January 16 and March 27, a wave of sectarian bombings in Baghdad killed hundreds of Sunnis and Shias. On March 30, the U.S. Senate set March 31, 2008 as a goal for the complete withdrawal of U.S. forces. On April 1, President Talabani said al-Sadr had ordered his Mahdi Army to stand down after six weeks of the new security push by joint U.S.-Iraqi forces. On April 18,car bombings by ISI killed more than 190 people. On June 10, U.S. forces advanced a strategy to arm Sunni groups to fight ISI.

June 13

The al Askari mosque in Samarra was bombed for the second time, destroying its minarets. On August 14, ISI bombings targeted communities of Yazidis, a non-Muslim religious minority, in northern Iraq. More than 400 were killed in the deadliest attack to date.

August 17

Shia and Kurdish leaders formed a political coalition to support Prime Minister Maliki after a Sunni faction quit the coalition government on August 1. On August 29, al-Sadr suspended military operations by his Mahdi Army militia for six months after street battles with Iraqi forces in Karbala.

November 5

Seven Americans were killed, making 2007 the deadliest year for U.S. forces since the 2003 invasion. By year’s end, 899 U.S. troops had died. On December 16, British forces handed over security for Basra province to Iraqi forces, ending five years of British control of southern Iraq. After the surge of U.S. troops, ISI was driven from Baghdad into Diyala, Salahideen, and Mosul. The organization lost the majority of its leaders, cells, and capabilities.


January 12

Parliament passed a bill allowing some former officers from Saddam Hussein’s Baath Party to take government jobs, collect government pensions, and return to public life.


Fighting broke out between the government and militias. On May 11, the government agreed to a ceasefire with al-Sadr. On April 21, Prime Minister Maliki announced a crackdown on armed militias and al-Sadr’s Mahdi Army.

October 1

The United States transferred administrative and operational control over the Sunni Awakening Council militias to the Iraqi government. The government also assumed security control over Anbar province. But the security situation worsened in the neighboring city of Mosul. In October, some 13,000 Christians fled threats and killings attributed to Sunni extremists.


January 1

The United States handed control over the Green Zone security district to the Iraqi government. On January 5, the United States opened a new embassy in the Green Zone, one of the largest it had ever built.  

February 27

President Obama announced a plan to end the U.S. combat mission in August 2010. By June 30, U.S. troops had withdrawn from some 150 bases and outposts in cities and villages, although some 130,000 still remained in the country. On July 31, the last British troops withdrew from Iraq to Kuwait.

August and December

ISI claimed responsibility for a series of bombings. Among the biggest was an August 19 bombing in Baghdad that killed more than 100. An October 25 bombing in Baghdad killed more than 150.On December 10, five suicide bombings in Baghdad killed at least 127.


March 7

Iraq held its second parliamentary elections since the 2003 U.S. invasion. No single coalition came close to winning majority seats. A new government was not formed because of political gridlock that played out over several issues for eight months. Maliki served as a caretaker prime minister.

April 18

Iraqi security forces, with the support of U.S. troops, killed ISI leaders Abu Omar al Baghadi and Abu Ayuub al Masri. In May, ISI selected Abu Bakr al Baghdadi as the new leader. Baghdadi had participated in the Sunni insurgency against U.S. forces in the 2000s, was detained by U.S. forces for 10 months at Camp Bucca in 2004, and eventually joined ISI.

May 9-10

A series of coordinated attacks carried out by ISI kill more than 100 people in Baghdad and other cities across Iraq.


President Obama officially ended the seven-year U.S. combat mission in Iraq. The last U.S. combat troops left on August 19, although U.S. military advisors and trainers remained in Iraq.

November 12

Iraqi President Jalal Talabani asked Maliki, the incumbent prime minister, to form a new government. On December 21, Parliament approved a new government, inclusive of all major political parties and ethnic groups, just four days before a constitutional deadline. Political infighting had delayed the formation process.


January 5-8

Shia cleric Moqtada al-Sadr returned to Iraq after three years of voluntary exile in Iran. In his first public statement, al-Sadr urged his followers to resist the “occupiers” of Iraq. On February 25, a “Day of Rage” swept the country as tens of thousands of Iraqis protested the newly elected government. Some 23 people were killed.


Abu Bakr al Baghdadi sent ISI operatives to build up a branch in Syria. One of them, Abu Muhammad al Julani, emerged as the leader of the new Nusra Front in January 2012.

December 18

The last U.S. troops pulled out of Iraq, officially ending the eight-year American military involvement in Iraq.

December 19

The government issued an arrest warrant for Vice President Tariq al Hashemi, a Sunni, for alleged ties to a group responsible for assassinations and bombings. The Sunni al Iraqiya bloc boycotted parliament, and its nine ministers stopped attending cabinet meetings, marking a rise in sectarian tensions. Iraqiya lawmakers ended their boycott in late January 2012, and Iraqiya ministers rejoined the cabinet in February 2012.


January 5-14

Attacks on Shia areas in Baghdad, Basra and Nasiriyah killed more than 100.

April 1

The Kurdistan Regional Government halted oil exports to Baghdadover thegovernment’s refusal to pay for the Kurdish oil sold, violating a 2011 agreement dividing income between the two parties.


ISI launched its “Breaking the Walls” campaign. It carried out 24 bombings and orchestrated prison breaks at eight facilities, freeing jihadists who had participated in AQI/ISI attacks in 2006 and 2007.The campaign continued through July 2013.

November 10

Iraq cancelled a $4.2 billion deal to buy military jets, helicopters, and missiles from Russia, due to concerns that the contract included corruption.

December 28

Massive protests spread throughout Iraq in Fallujah, Ramadi, and Anbar province, all Sunni-majority areas. Tens of thousands of Sunnis demonstrated against the Shia-dominated government of Maliki.



The Sunni insurgency intensified across Iraq. Sectarian violence, kidnappings, and bombings escalated levels not seen since 2006 and 2007. On April 8, Baghdadi announced the absorption of the al Qaida-backed Nusra Front in Syria. He said the combined group would be known as the Islamic State in Iraq and Syria (ISIS). But the leader of the Nusra Front, Julani, rejected the merger and instead declared allegiance to al-Qaida. In April 2013, the Hawija region’s anger at the government exploded after the Iraqi Army attacked Sunni protestors exercising what they considered civil disobedience. Up to 200 civilians were killed and at least 150 were injured. Such incidents fueled the surge of ISIS in the area the following year. By June 2014, ISIS had seized Hawija and much of southern Kirkurk, often with help from disaffected local residents.

July 21

On July 21, 2013, ISIS launched its second 12-month campaign, “Soldier’s Harvest,” on Iraqi security forces and to capture territory. On July 22, ISIS attacked Abu Ghraib prison freeing between 500 and 1000 inmates, including senior al-Qaida leaders and other militants.  

September 21

Iraqi Kurdistan held parliamentary elections for the first time in 22 years. Kurdistan President Massoud Barzani’s KDP Party remained the dominant political power of the sub-region. The PUK suffered significant loses and the new Goran movement gained votes, reflecting a shift in the region’s politics.  

September 29

ISIS launched a wave of attacks in Erbil, the Kurdish capital, in response to the Iraqi Kurds fighting jihadis in Syria. These attacks were the first in the city since 2007. In October, some 900 people were killed in attacks, many attributed to ISIS. On December 30, ISIS militants in Iraq seized Fallujah and parts of Ramadi, both major cities.


January 1-6

ISIS overran parts of the towns of Anbar and Ramadi. In January,ISIS also seized the Syrian city of Raqqa, which it declared the caliphate’s capital. On February 3,al-Qaida central disavowed any connection to ISIS. In a statement posted on jihadist web forums, it said al-Qaida “was not informed or consulted about ISIS’s establishment. It was not pleased with the duplication of its missions, and thus ordered its suspension.”

April 30

Prime Minister Maliki’s Dawa Party won the first election since the withdrawal of U.S. troops, but fell short of a majority. For the next four months, political gridlock delayed formation of a new government.

June 10

ISIS militants seized Mosul, Iraq’s second largest city some 250 miles north of Baghdad. On June 12, Iran deployed forces to fight ISIS in Iraq, and helped Iraqi troops regain control of most of Tikrit. On June 18, Iraq asked the United States to conduct airstrikes against ISIS. On June 21, ISIS seized the strategic border crossing between Syria’s Deir Ezzor province and Iraq, as well as three other Iraqi towns. With much fanfare, it declared the failure of colonial borders defined by Europeans in the Sykes-Picot agreement a century earlier.

June 13

Grand Ayatollah Ali al-Sistani, the Shia world’s top marja, responded to the Sunni jihadi movement with a fatwa calling Iraqis to take up to arms. Tens of thousands of men, mostly Shia, joined new and old armed groups, many supported by Iran. Prime Minister Maliki signed a decree creating the Commission for the Popular Mobilization Forces (PMF). More than 60 armed groups eventually merged under the PMF umbrella. They were dominated by Shias and often Iranian-backed, but they also included some Sunnis and Christians. They became pivotal fighters in the war against ISIS which helped them attain the status that allowed them to fight alongside the Iraqi armed forces.  

June 29

ISIS announced the establishment of a caliphate and rebranded itself as the “Islamic State.” Abu Bakr al-Baghdadi was declared the caliph, the “leader for Muslims everywhere.” Spokesperson Abu Muhammad al-Adnani announced that the “legality of all [other] emirates, groups, states, and organizations, becomes null by the expansion of the caliph’s authority and arrival of its troop to their areas.”  

August 2-3

ISIS conquered the towns of Sinjar and Zumar, forcing thousands of Yazidis to flee their homes. ISIS was accused of extensive human rights abuses, including rape of Yazidi women and mass executions. ISIS also seized Mosul dam, a critical piece of infrastructure responsible for controlling the flow of the Tigris River and supplying electricity to more than a million people.  

August 7

President Obama announced the beginning of air strikes against ISIS in Iraq to defend Yazidi citizens stranded in Sinjar.

August 15

Prime Minister Maliki resigned. On September 8, Parliament approved a new government formed by new Prime Minister Haider al-Abadi.

September 10

The United States announced the creation of a broad international coalition to defeat ISIS. Seventy-nine nations and institutions, including NATO, the European Union and the Arab League, eventually joined it. Some contributed warplanes for aerial strikes, others logistical support or trainers.

December 2

Iraq’s government signed a deal with the Kurdistan Regional Government to share the country’s oil and military resources to defeat ISIS.


March 16

Iraq deployed 30,000 forces in a major offensive to recapture Tikrit from ISIS. On May 17, ISIS took over Ramadi

October 15

Iraq recaptured the Baiji refinery, the country’s largest oil refinery, from ISIS.On November 13,Kurdish forces seized Sinjar from ISIS. On December 27, Iraqi military forces seized Ramadi from ISIS.

October 22

A member of a U.S. special operations force was killed during an ISIS hostage rescue mission in northern Iraq. He was the first American to die in ground combat with ISIS. On December 1, Defense Secretary Ashton Carter announced that U.S. special operations forces would be sent to Iraq to support Iraqi and Kurdish fighters and launch targeted operations in Syria. On December 10, U.S. officials announced that airstrikes killed ISIS Finance Minister Abu Saleh and two other senior leaders in Tal Afar.


April 30

Supporters of al- Sadr broke into the Green Zone and stormed Parliament. Protesters demanded a new government to fight corruption after weeks of political gridlock and turmoil because parties insisted on appointing ministers along sectarian lines.  

May 23

Iraqi forces, aided by U.S. and coalition airstrikes, advanced on Fallujah, which ISIS had held since 2014.On June 26,the Iraqi army retook Fallujah. On July 6, ISIS killed 250 people in a suicide bomb attack in Baghdad. On October 16, Iraq launched a campaign to liberate Mosul from the Islamic State. OnOctober 22, Iraqi forces captured Qaraqosh, a Christian area southeast of Mosul, which had been under ISIS rule since 2014.On October 25, ISIS took control of half of the western Iraqi town of Rutba, located near the Syrian and Jordanian borders. OnOctober 28, ISIS fighters used tens of thousands of men, women and children as human shields in Mosul to prevent Iraqi troops from advancing.

November 26

Iraq’s parliament legalized the PMF, armed groups that emerged after ISIS seized territory in 2014. The vote was unanimous. “Those heroic fighters, young and old, need our loyalty for the sacrifices they have made,” Abadi’s office said.

November 1

The Iraqi Counterterrorism Service captured the Mosul state television station from ISIS. It was the first building taken from ISIS since the Mosul campaign began. On November 15, an Iraqi interior ministry spokesman announced that one-third of eastern Mosul had been liberated.

December 5

Abi al-Hassan al-Muhajer was named the new spokesman for ISIS in an online audio message. The previous spokesman, Abu Mohammad al-Adnani, was killed in an airstrike at the end of August in Syria. In his first statement as spokesman, al-Muhajer urged ISIS sympathizers to carry out new attacks and for fighters to stand their ground in Iraq.


January  23-24

Government forces took complete control of eastern Mosul from ISIS, 100 days after the campaign started. On February 19, U.S.-backed Iraqi forces launched a ground offensive against ISIS in western Mosul.

February 24

Iraq launched air strikes against ISIS targets inside Syria for the first time after coordinating with Damascus. Between March 14 and 16, Iraqi forces killed the Islamic State’s commander of Mosul. On March 16,Iraqi forces besiegedISIS fighters in Mosul’s Old City. On March 31,the Islamic State’s deputy leader Ayad al-Jumaili was killed in an air strike. On May 18,PMF captured the Sahl Sinjar airbase from the Islamic State in the western desert about 40 miles from the Syrian border. On May 26, U.S. airstrikes killed three senior level ISIS military leaders—Mustafa Gunes, Abu Asim al-Jazeri and Abu Khattab al-Rawi. On May 31,ISIS fighters in Mosul closed off the Grand al-Nuri Mosque in preparation for their last stand. On June 14, ISIS fighters launched a counterattack in west Mosul against Iraqi forces. On June 21,ISIS destroyed the Grand al-Nuri Mosque, where Abu Bakr al-Baghdadi had declared the Islamic caliphate in June 2014. Iraqi troops captured the remains of the mosque on June 29 after an eight-month campaign. On July 9, Iraqi Prime Minster al-Abadi declared victory over ISIS in Mosul. On August 26, Iraqi forces captured Tal Afar near the Syrian border.  

September 25-October 16

In a regional referendum,92 percent of Iraqi Kurds voted for independence. It was organized by Kurdistan Regional Government as a step toward statehood. The turnout was more than 72 percent. Iraq’s central government responded by using military force to reassert control over Kurdish-controlled territories—including the oil-rich city of Kirkuk—which are disputed between the KRG and the central government.

September 21

Iraqi forces launched an offensive on Hawija, one of the last territories under Islamic State. During the first week of October, hundreds of ISIS militants surrendered to Kurdish authorities after being driven from Hawija. On November 2,Iraqi forces retook the Akkas gas field near the Syrian border. On November 3, Iraqi forces recaptured al-Qaim, one of the Islamic State’s last territories. On November 17, Iraqi forces captured the border town of Rawa, the last remaining town under ISIS control in Iraq.

December 9

Iraqi Prime Minister al-Abadi declared victory over the Islamic State. “Honorable Iraqis your land has been completely liberated. The dream of liberation is now a reality,” he said on national television.

December 27

The U.S.-led coalition reported that less than 1,000 ISIS fighters remained in Iraq and Syria.


April 22

Iraq airstrikes targeted ISIS military positions and its explosives factory with in Syria. On May 1,the U.S.-backed Syrian Democratic Forces (SDF) announced a new effort to reclaim the last ISIS held territory in Syria. “ISIS retains a significant presence near the Iraqi borders from which it seeks to retain safe haven to plan attacks around the world and expand its territory in Syria and Iraq,” an SDF statement said. “Over the coming weeks, our heroic forces will liberate these areas, secure the Iraq-Syria border, and end the presence of ISIS in eastern Syria once and for all.” On May 6,the Iraqi Air Force struck ISIS commanders in Syria. On May 9, a group of senior ISIS officials hiding in Turkey and Syria were captured in a cross-border U.S.-Iraqi sting.

May 12

Iraq held parliamentary elections. The political bloc led by al-Sadr won the majority. It was an unlikely alliance of al-Sadr’s followers, communists and other secular groups. On June 7, Parliament ordered a nationwide recount of May election results after the emergence of widespread allegations of election fraud. In August, the results were finalized. Al-Sadr’s bloc took 54 seats, six more than a group of Iran-backed Shia leaders, and 12 more than Abadi’s block.


Protests spread throughout the Shia majority city Basra, in southern Iraq, over unemployment, shortages of clean water and electricity, and widespread corruption. Protesters burned government buildings and political offices, including the Iranian consulate. The United States ordered the evacuation of its consulate after rockets were launched in its direction. Secretary of State Mike Pompeo held Iran and its allies responsible.

September 15

Parliament elected Sunni lawmaker Muhammad al-Halbusi as its new speaker. At age 37, al-Halbusi was the youngest speaker in Iraqi history. He was jointly supported by Hadi al-Amiri’s Fatah (Conquest) Coalition, a group of Iran-backed groups that ran in the 2018 elections and influential Sunni politicians like Jamal Karbouli. On October 2, Parliament elected veteran Kurdish politician Barham Salih to the presidency. On the following day, he asked Adil Abd al-Mahdi, a 76-year-old economist and veteran Shia politician, to be the prime minister. The selection of Salih and Mahdi, respected technocrats, signaled a shift toward a more conciliatory and less sectarian method of governing. The Iraqi people, however, remained skeptical about their ability to deliver reform and practical changes in their lives.

September 30

The KRG held parliamentary elections. The ruling KDP came in first place with 45 seats while the rival PUK came in second place with 21 seats. Parliament has 111 seats, 11 of which are reserved for minority groups.

October 24

Prime Minister Mahdi was sworn in with a partial cabinet of 14 ministers. He was the first premier not affiliated with a party or political bloc when he was nominated, a significant shift for Iraq. Political factions failed to reach consensus on the remaining eight posts, which included the ministries of defense, justice and immigration and interior. Lawmakers were slated to vote on the vacancies on December 4, but the session was cut short after opponents of Mahdi’s picks banged on tables and shouted “illegitimate.” Five more ministries have been confirmed, but defense, interior, and justice remain unfilled due to strong disagreements.


March 11-13

Iranian PresidentHassan Rouhani made his first official trip to Baghdad alongside Foreign Minister Javad Zarif. Rouhani held a high-profile meeting with Grand Ayatollah Ali Sistani, Iraq’s most revered religious authority, as well as Prime Minister Mahdi and President Salih. During the visit, Iranian and Iraqi officials signed memorandums of understanding on oil and gas, land transport, railways, agriculture, industry, health, and banking. Rouhani’s visit was largely seen as an effort to boost trade with Iraq and circumvent U.S. sanctions.

May 7

Secretary of State Mike Pompeo made an unannounced visit to Baghdad hours after telling reporters that the United States was concerned about Iraqi sovereignty because of increasing Iranian activity. He told Iraqi leaders, including Prime Minister Mahdi and President Salih, that Washington did not “want anybody interfering in their country,” and asked them to protect U.S. troops in Iraq.

May 15-June 18

Amid rising tensions between the United States and Iran, the State Department ordered the departure of non-emergency U.S. government employees from Iraq, both at the embassy in Baghdad and consulate in Erbil. In the first half of 2019, unidentified militias had launched eight rocket attacks on U.S.-linked facilities in Iraq, including strikes on coalition training facilities in Taji and Mosul on June 17-18.


Some 10 months after Kurdistan Regional Parliament elections, lawmakers elected Nechirvan Barzani—a former KRG prime minister and KDP leader—to the region’s presidency. His party’s rival, the PUK, boycotted the vote, but senior PUK leaders eventually decided to attend the swearing in ceremony. Iraqi President Salih and Speaker of the Council of Representatives al-Halbusi, among other officials from Baghdad, also attended the ceremony on June 10. The election was positively received by the international community and Iraqi leaders because the Kurdish region’s presidency had been vacant since Masoud Barzani stepped down in 2017. Masrour Barzani, the former chancellor of the Kurdistan Region Security Council, was named for the post of prime minister and was tasked with forming a cabinet.


Mass protests spread in Baghdad and southern provinces over the government and political class’s failure to deliver basic services, provide jobs, fight corruption, and more. To disperse the protests, reports indicate that Iraqi security forces and armed groups linked to Iran killed over 100 protestors and injured more than 6,000 during the first week. The demonstrators’ demands expanded to include calls for regime change, the resignation of Prime Minister Adel Abdul Mahdi, early elections, a push back against Iranian influence, and accountability for the killing of peaceful protesters. The prime minister rejected calls for his resignation and instead proposed administrative reforms, including cabinet reshuffles. Iraqi President Barham Salih proposed a new election law as an attempt to respond to protestors’ demands of more inclusive and fair elections.

October 26

The leader of ISIS, Abu Bakr al-Baghdadi, was killed by a U.S. special forces air raid in Idlib in northwest Syria. President Donald Trump confirmed the success of the two-hour night operation that targeted al-Baghdadi’s safe house in Syria.


Confrontations between protestors and security forces intensified, leaving more than 400 protestors dead and thousands more wounded in the first two months. On November 27, anti-government demonstrators who opposed Iranian influence in Iraq burned down the Iranian consulate in Najaf. Prime Minister Adel Abdul Mahdi announced his resignation in response to a call by Iraq’s most prominent Shia cleric, Grand Ayatollah Ali Sistani, for a change in leadership.

December 27

Kataeb Hezbollah, which is part of the Popular Mobilization Forces, carried out a rocket attack that killed a U.S. defense contractor and wounded four U.S. military personnel at an Iraqi military base in the province of Kirkuk. Two days later, the U.S. launched retaliatory airstrikes on Kataeb Hezbollah facilities in Iraq and Syria, killing over 20.

December 31

Kataeb Hezbollah, other Iran-backed groups, and leaders of some units of the Popular Mobilization Forces organized a siege on the U.S. Embassy in Baghdad. No U.S. casualties were reported. Following the attack, U.S. Secretary of Defense Mark Esper announced the deployment of an infantry battalion, totaling about 750 soldiers from the Army’s 82nd Airborne Division, to the Middle East.


January 3

A U.S. drone strike at the Baghdad airport killed Qassem Soleimani, the powerful commander of Iran’s Quds Force, and Abu-Mahdi al-Muhandis, leader of Kataeb Hezbollah and deputy chief of the Popular Mobilization Forces.

January 5

Prime Minister Adil Abdul Mahdi urged Iraqi legislators to end U.S. troop presence in Iraq. The Iraqi Council of Representatives passed a non-binding resolution to end foreign military presence in Iraq. Most Kurdish and Sunni members boycotted the vote. The U.S.-led coalition halted its operations against the Islamic State as American forces prepared for Iranian retaliations. Operations were resumed 10 days later.

January  8

In retaliation for the killing of Qassem Soleimani, Iran launched more than a dozen missiles at two Iraqi bases housing U.S. troops. The attack damaged the facilities, but the United States initially reported that no U.S. or Iraqi personnel were harmed. In February, the U.S. military disclosed that more than 100 troops were diagnosed with brain injuries following the Iranian strike. On January 27, following a short period of de-escalation, the U.S. Embassy in Baghdad was hit by three rockets that landed in the embassy and its surroundings. The attack injured at least one person and was not claimed by any group.

January 9

Prime Minister Adil Abdul Mahdi called on U.S. Secretary of State Michael Pompeo to send delegates to Iraq to discuss mechanisms for the withdrawal of U.S. troops following the Iraqi Council of Representatives’ resolution regarding the withdrawal of foreign troops from Iraq. A day later, the State Department said that the U.S. would not hold discussions with Iraq regarding military withdrawal.

January 24

Thousands of Iraqi protesters gathered in al-Hurriyah Square in Baghdad and near the main university to protest continued U.S. military presence. The protests came as a response to Shia cleric Moqtada al-Sadr’s call demanding U.S. troop withdrawal from Iraq.

February 1

Former Communications Minister Mohammed Tawfiq Allawi was appointed by President Salih as prime minister-designate to form a new cabinet. Allawi’s nomination sparked uproar on the streets by demonstrators who were wary of his role under former Prime Minister Nuri al-Maliki’s government. After failing to receive a vote of confidence in parliament for his cabinet nominees, Allawi withdrew his candidacy on March 1. Former Prime Minister Abdul-Mahdi continued to serve as the caretaker during the deadlock.

February 24

The Iraqi Ministry of Health recorded the first case of COVID-19 in Najaf governorate, and in the following days reported several other cases in Iraq—the majority of whom were infected after recently visiting Iran. On February 26, the Ministry of Health instituted a ban on travel to and from nine countries, including Iran and China. The first fatality due to COVID-19 was recorded on March 3 in the city of Sulaymaniyah in the Kurdistan region of Iraq. On March 15, the Iraqi government began imposing multiple provincial curfews and a ban on public gatherings to slow the spread of the virus.

March 11

Thirty Katyusha rockets were fired at Camp Taji north of Baghdad, killing two U.S. service members and one British service member and injuring 14 others. No group claimed responsibility for the attack, but Iran-backed groups, including Kataeb Hezbollah (KH), lauded the operation. In retaliation for the attack on Camp Taji, the U.S. struck five weapon storage facilities belonging to KH early on March 13. Iraqi military officials, however, said the strikes damaged an unfinished civilian airport, and killed three Iraqi soldiers, two police officers, and a civilian worker. On March 14, at least 25 rockets hit Camp Taji again, injuring three U.S. soldiers and two Iraqi soldiers.

March 17

President Salih appointed former Najaf Governor Adnan al-Zurfi as prime minister-designate, after the first candidate Mohammad Tawfiq Allawi’s withdrawal on March 1. Al-Zurfi was the head of the Nasr parliamentary grouping of former Prime Minister Al-Abadi. After three weeks of deadlock and opposition from the Shia groups, al-Zurfi withdrew citing “internal and external reasons.”

April 9

President Salih appointed the head of Iraq’s intelligence service, Mustafa al-Kadhimi, as prime minister-designate, after the first two appointees withdrew. On May 6, parliament approved al-Kadhimi as the new Iraqi prime minister after almost six months of a caretaker government.

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