Please note: the article for the post-invasion violence in Iraq is now to be found under the name "Iraqi Insurgency" in the database. The source for the number of fatalities of this article:

Source: Uppsala Conflict Data Program (Date of retrieval: 12/12/07) UCDP Conflict Encyclopedia, Uppsala University

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The 2003 invasion of Iraq, also called simply the Iraq War or Operation: Iraqi Freedom, was a war that began March 20, 2003, fought between a group of troops consisting primarily of American and British, but also Polish, Australian and several other nations’ forces, and Iraq.

The invasion began without the explicit authorization of the United Nations Security Council, and most legal authorities take the view that the action violated the U.N. Charter. The Bush Administration has cited Security Council resolutions from early 1990s as legal justification, though there is no clear support in any of them for military action against Iraq.

After approximately three weeks of fighting, Iraq was occupied by coalition forces and the rule of Saddam Hussein and his Ba’ath Party came to an end. Subsequently, the period known as post-invasion Iraq began. Approximately 250,000 United States troops, with support from 45,000 British, and smaller forces from other nations, collectively called the "Coalition of the Willing", entered Iraq primarily through a staging area in Kuwait. Plans for opening a second front in the north were abandoned when Turkey officially refused the use of its territory for such purposes. Forces also supported Iraqi Kurdish militia troops, estimated to number upwards of 50,000.

Facing them was a large but poorly equipped military force. The regular Iraqi army was estimated at 280,000–350,000 troops, with four Republican Guard divisions with 50,000–80,000 troops, and the Fedayeen Saddam, a 20,000–40,000 strong militia, who used guerrilla tactics during the war. There were an estimated thirteen infantry divisions, ten mechanized and armored divisions, as well as some special forces units. The Iraqi Air Force and Navy played a negligible role in the conflict.

On 17 March 2003, in his Address to the Nation, U.S. President George W. Bush demanded that Iraqi President Saddam Hussein and his two sons Uday and Qusay leave Iraq, and gave them a 48-hour deadline; Iraqi President Saddam Hussein refused to leave.[1] (http://www.whitehouse.gov/news/releases/2003/03/iraq/20030317-7.html) The next day Bush’s spokesman Ari Fleischer announced that the U.S. would invade Iraq whether Saddam Hussein left or not, stating that "the bottom line is, a coalition of the willing will disarm Saddam Hussein’s Iraq, no matter what." [2] (http://www.whitehouse.gov/news/releases/2003/03/20030318-4.html)

United States military operations were conducted under the name Operation Iraqi Freedom. United Kingdom military operations as Operation Telic, and Australian operations as Operation Falconer.