At 0315GMT, after giving Saddam Hussein a 48 hour ultimatum to leave Iraq, President Bush announces coalition forces have begun striking "selected military targets" in Iraq.
"America's freedom will be defended, and freedom will be brought to others," he says.
In what is labelled a campaign of 'shock and awe', the US initiates "precision" bombing raids on major cities including Baghdad in an attempt to force an Iraqi surrender.
US military commanders say they have secured Baghdad's airport as Saddam Hussein appears on television urging Iraqis to defend their capital.
US-led forces enter Baghdad. In pictures seen around the world, a statue of Saddam Hussein in central Baghdad is brought crashing down. The takeover is followed by widespread looting across the country.
Revealed in the form of a deck of cards, the US military unveils a list of the 55 most wanted members of the former Saddam regime.
US forces capture Saddam's hometown of Tikrit. Commanders say the capture means that the war is coming to an end. At the same time the US announces it is pulling two of its three aircraft carriers out of the Gulf.
British forces were the main non-
US contribution to the coalition
Iraq’s army is disbanded by the Coalition Provisional Authority – a post war civil administration under the authority of retired US General Jay Garner charged with overseeing reconstruction of the country.
Standing on the deck of a US aircraft carrier returning from the Gulf - and in front of a banner reading "Mission Accomplished" - President Bush announces the end of "major combat operations". But he warns that “difficult work” remains to be done.
President Bush appoints Paul Bremer as the top civil administrator in Iraq.
The first Saddam-era mass graves are discovered near Baghdad, containing the bodies of an estimated 15,000 Shia civilians.
Bush welcomes returning troops
with a controversial claim
Following a change of government in Madrid, Spain becomes the first major member of the US-led coalition to withdraw its troops from Iraq.
The UN backs a resolution to lift economic sanctions against Iraq and votes to recognise the UK and USA as Iraq’s temporary occupying powers.
Speaking to US soldiers in Qatar, President Bush vows to "reveal the truth" about Iraqi weapons of mass destruction.
Composed of 25 Iraqis appointed by the US-led coalition, the Iraqi General Council (IGC) meets for the first time, tasked with drafting a new constitution.
Saddam Hussein’s sons, Uday and Qusay, are killed in a fierce gun battle with US troops in the city of Mosul. US forces are thought to have acted on a tip-off after offering a bounty of $15 million for each of the two brothers.
A truck bomb destroys the UN headquarters in Iraq, leaving over 100 injured and 20 dead, including the top UN envoy, Sergio Vieirra de Mello.
A deadly truck bomb targets UN
headquarters in Baghdad
A car bomb attack in Najaf kills Shia politician Ayatollah Mohammed Baqr al-Hakim and 90 others.
David Kay, a former UN weapons inspector put in charge of the US hunt for Iraq's WMDs, admits no such weapons can be found and that they probably never existed in any significant form.
The UN Security Council votes in favour of a US revised blueprint for the future of Iraq - a resolution that preserves the US administration’s dominance.
The US congress authorises President Bush’s request for $87 billion to continue the occupation of Iraq.
The IGC announces that coalition forces will transfer power to a transitional government in June 2004 with a plan to establish a fully sovereign government by 2005.
US forces capture Saddam Hussein in an underground hideout near his hometown of Tikrit. Pictures are released showing an unkempt, heavily bearded Saddam being examined by US medical officers.
Saddam was found hiding out in
his hometown of Tikrit
David Kay resigns as head of the US-led Iraq Survey Group saying he does not believe WMD stockpiles will be found in Iraq. "I don't think they existed," he tells the US Senate Armed Services Committee (SASC), adding "we were all wrong and that is most disturbing."
Bowing to growing public pressure the US and UK governments set up inquiries into the reasons behind the invasion of Iraq.
First reports emerge of US soldiers abusing Iraqi prisoners.
A car bomb targets a police station in the Shia town of Iskandariya leaving at least 45 dead and dozens wounded – part of an escalating wave of attacks on Iraqi police and army recruitment centres.
Opposition to the US occupation
grows with a wave of car bombs
On the first anniversary of the start of the war, President Bush describes the 2003 US-led invasion as the "day of deliverance" for the Iraqi people.
US troops begin a month-long siege of the northern city of Falluja, a hotbed of resistance against the occupation. Much of the city is devastated, with heavy casualties among civilians and fighters.
An Italian security guard becomes the first western hostage to be murdered.
Oil facilities are targeted by fighters, crippling the revival of Iraqi oil production.
Photographic evidence emerges of abuse of Iraqi prisoners by US soldiers at Abu Ghraib prison near Baghdad.
US forces begin to leave Fallujah a month after they went in and an uneasy truce is declared. Doctors say at least 600 people have died in a month of fierce fighting.
Images of prisoner abuse sent
shockwaves around the world
A suicide bomber kills Ezzadine Salim, the holder of the rotating presidency of the Iraqi Governing Council.
The independent 9/11 Commission in the US say it finds “no credible evidence” of a link between Iraq and al-Qaida.
In a surprise move two days ahead of schedule, the US hands over sovereignty to the interim government, headed by Iyad Allawi, the interim prime minister. Meanwhile Saddam Hussein is transferred into Iraqi legal custody.
Saddam Hussein appears in court for the first time to hear charges against him of committing war crimes and crimes against humanity.
The UK government is cleared by Lord Butler of any deliberate attempt to mislead the British public over the invasion of Iraq.
Concluding four days of talks the Iraqi National Council appoints a 100-member national assembly overseeing Allawi’s interim government until elections can be held.
The latest in a series of attacks on army and police posts leaves 40 army recruits dead, further undermining US efforts to transfer security responsibilities to Iraqi forces.
A British study reports that the Iraqi civilian death toll since invasion may be as high as 100,000, mostly as a result of air raids by US-led forces. (A later study in July 2005 by NGO Iraq Body Count says puts the figure at 25,000 dead.)
The human cost for ordinary
Iraqis remains unclear
Thousands of US troops begin another large offensive against fighters in Falluja. A week of intense fighting follows, during which US commanders claim to have killed more than 1,200 insurgents holed up in the city since April
Iraqi officials set 30 January 2005 as the date for Iraq’s first general election.
The number of US troops killed since the start of the war in Iraq hits 1000.
Army reserve specialist Charles Graner, accused of instigating the abuse of prisoners at Abu Graib jail, is jailed for 10 years by a military court in Texas. He was also given a dishonourable discharge from the army. Graner said he was following orders to "soften up" prisoners.
With a turnout nearing 8 million, Iraqis vote for a Transitional National Assembly in what is branded the first free election since the removal of Saddam.
In the worst attack of its kind since the fall of Saddam, at least 114 people are killed by a massive car bomb in Hilla, south of Baghdad. Most of the victims had been waiting to apply for government jobs.
After months of wrangling, members of the Transitional National Assembly select Kurdish leader Jalal Talabani as president and Shia Ibrahim al-Jaafari as prime minister.
A new constitution is endorsed by Shia and Kurdish negotiators, but not by the Sunni representatives. Thousands of Sunnis across Iraq stage protests rejecting the constitution.
In the deadliest single incident in Iraq since the US invasion, more than 1000 people die in a stampede of Shia pilgrims in northern Iraq.
More than 180 people are killed in a series of attacks in Baghdad, including a car bomb attack on a group of workers in a mainly Shia district. Abu Musab al-Zarqawi, the Jordanian-born Sunni militant and leader of al-Qaida in Iraq, declares war on Iraqi Shia.
Defying violence and security threats, 80% of the population vote in a referendum on a draft constitution turning Iraq into an Islamic federal democracy. With 78% voting in favour, the result paves the way for elections in December.
Amid tight security Saddam Hussein's trial begins in Baghdad. Saddam, along with seven associates, plead not guilty to charges that they ordered the killing of 143 Shia men in Dujail in 1982.
Saddam goes on trial
President Bush says he believes around 30,000 Iraqis have been killed since the US-led invasion. The first time he has put a concrete figure on the human cost of the war.
Iraqis turn out in large numbers to vote for the country's first full term government since the invasion. Despite fears, there are only relatively minor incidents of violence and Sunni Arabs, who largely boycotted the January election, participated in large numbers.
In the wake of the Iraqi vote, President Bush declares Iraq a new ally in the war on terror and a force for democracy in the Middle East.
Sunni Arab and secular parties threaten to boycott the new parliament, complaining of widespread fraud in the December 15 election that saw the main Shia-led coalition maintain its dominance.
As discussions continue between Kurdish, Shia and Sunni groups on the formation of a new coalition government, suicide bomb blasts in the cities of Ramadi and Karbala leave at least 120 people dead.
The Shia-led United Iraqi Alliance is declared the winner of the December 15 parliamentary elections, but fails to secure an absolute majority.
A bomb attack badly damages the Askariya shrine in the city of Samarra. Although no-one is killed, the attack on one of Shia Islam's holiest sites sparks a wave of sectarian violence and renews fears of a descent into civil war.
Iraq's parliament elected on December 15 meets for the first time, but breaks up again without conducting any business as talks on forming a national unity government remain deadlocked.