Republic of Iraq. Post-invasion insurgency β Civil war β Insurgency β The invasion of Iraq [ b ] was the first stage of the Iraq War. The invasion began on 20 March and lasted just over one month, [ 24 ] including 26 days of major combat operations, in which a United States-led combined force of troops from the United States, the United Kingdom, Australia and Poland invaded the Republic of Iraq.
Twenty-two days after the first day of the invasion, the capital city of Baghdad was captured by coalition forces on 9 April after the six-day-long Battle of Baghdad. This early stage of the war formally ended on 1 May when U. President George W. Bush declared the "end of major combat operations" in his Mission Accomplished speech , [ 25 ] after which the Coalition Provisional Authority CPA was established as the first of several successive transitional governments leading up to the first Iraqi parliamentary election in January The coalition sent , troops into Iraq during the initial invasion phase, which lasted from 19 March to 1 May.
Thirty-six other countries were involved in its aftermath. In preparation for the invasion, , U. According to U. About 5, largely unusable chemical warheads , shells or aviation bombs were discovered during the Iraq War, but these had been built and abandoned earlier in Saddam Hussein 's rule before the Gulf War. The discoveries of these chemical weapons did not support the government's invasion rationale. On 15 February , a month before the invasion, there were worldwide protests against the Iraq War , including a rally of three million people in Rome, which the Guinness World Records listed as the largest-ever anti-war rally.
The invasion was preceded by an airstrike on the Presidential Palace in Baghdad on 20 March The following day, coalition forces launched an incursion into Basra Governorate from their massing point close to the Iraqi-Kuwaiti border. While special forces launched an amphibious assault from the Persian Gulf to secure Basra and the surrounding petroleum fields, the main invasion army moved into southern Iraq, occupying the region and engaging in the Battle of Nasiriyah on 23 March.
Massive air strikes across the country and against Iraqi command and control threw the defending army into chaos and prevented an effective resistance. On 26 March, the rd Airborne Brigade was airdropped near the northern city of Kirkuk , where they joined forces with Kurdish rebels and fought several actions against the Iraqi Army , to secure the northern part of the country.
