Origin of the conflict
Iraq became a British protectorate in 1920 and covered three former provinces of the Ottoman Empire. These different territories had originally little in common, so the British installed a king that promoted Arab nationalism to unify the population. Large parts of the population were excluded, since the political elite was dominated by the Sunni Muslim minority, which was educated and had worked for the Ottoman administration. A military revolt in 1958, caused by the disapproval of the lack of development in Iraq, overthrew the monarchy and resulted in conflict in 1959 and 1963. Eventually a socialist one-party state was established in 1968. The government suppressed opposition and many opposition leaders left the country. In Iran exiled Shia Muslim Iraqis (SCIRI: Supreme Council for the Islamic Revolution in Iraq) fought against the Iraqi government in 1982-84, 1987, and 1991-96.

Conflict over Kurd areas
The Kurd areas in the north of the country were disputed since the formation of Iraq. Local leaders soon started arguing for the establishment of an independent Kurdistan. This led to conflict over these areas in 1961-70, 1973-93, and 1996. ?Read the article about the Kurdish conflict

Conflict with Kuwait
Iraq invaded Kuwait in 1990. It claimed that the territory should be considered a province of Iraq. The UN criticized the invasion and Kuwait received military support.

War in Iraq
After claims that Iraq was developing weapons of mass destruction and that the government was supporting terrorism,  the invasion began in 2003. The coalition that invaded the country was led by the US and got support from the UK and Australia, together with some forty other countries. After the Iraqi government of Saddam Hussein was defeated, many troops remained in the country to support the new government in the conflict that existed in the country.


Chronological timeframe

1920:
•    Ottoman rule over Iraq lasted until the World War I, when the Ottomans sided with Germany and the Central Powers.
•    On 11 November it became a League of Nations mandate under British control with the name "State of Iraq".

1932:
•    Britain granted independence to Iraq, on the urging of King Faisal.

1941-1947:
•    Iraq became subjected to military occupation by the British, since it was deemed strategically important for the Second World War effort.

1980-1988:
•    Iran-Iraq War (Firstl Gulf War). The war began when Iraq invaded Iran on 22 September, after a long history of border disputes and fears of Shia insurgency among Iraq's long-suppressed Shia majority influenced by the Iranian Revolution.

1990–1991:
•    Persian Gulf War (Second Gulf War)
•    Iraq faced an economic disaster after the end of the Iran–Iraq War. Saddam Hussein looked to the oil-rich neighbour of Kuwait as a target to invade, to use Kuwait’s resources and money to rebuild Iraq's economy.
•    The UN agreed to pass economic sanctions against Iraq and demanded its immediate withdrawal from Kuwait.

1996:
•    Conflict about the Kurd areas, as in 1961-1970 and 1973-1993.

2002:
•    Bush warned of military action unless inspections were allowed to progress unfettered. Iraq reluctantly agreed to new inspections in late 2002. The weapons inspections did not uncover any WMD in Iraq.

2003:
•    US, UK and Spain proposed to give Iraq a deadline for compliance with previous resolutions and to enforce this by the threat of military action.  Especially France, Germany, Canada and Russia were opposed to military intervention in Iraq.
•    The invasion of Iraq began, Led by US army General Tommy Franks. Apart form the US, UK and Australia, about forty other governments (the coalitions of the willing) provided troops, equipment, services, security, and special forces.
•    Bagdad fell on the 9th of April, ending President Hussein's 24-year rule.
•    Sadam Hussein was captured on December 13.

2004:
•    The most serious fighting of the war so far began on March 31, 2004, when Iraqi insurgents in Fallujah ambushed a Blackwater USA convoy. Four men were killed, their bodies were dragged from their and their burned corpses hung over a bridge crossing the Euphrates.
•    This led to the First Battle of Fallujah in April (the unsuccessful "pacification" of the city).
•    The abuse of prisoners at Abu Ghraib received international media attention in April.
•    In November the bloodiest battle of the war so far took place: the Second Battle of Fallujah.

2005:
•    Iraqis elected the Iraqi Transitional Government on January 31 2005, in order to draft a permanent constitution.
•    May was the bloodiest month since the invasion and suicide bombers were active throughout the country. Hopes for a quick end to the insurgency and a withdrawal of US troops were dashed.
•    The new Iraqi constitution was ratified in a referendum at October the 15th.
•    In December an Iraqi national assembly was elected, with participation from the Sunnis as well as the Kurds and Shia.
•    Insurgent attacks increased in 2005 with 34,131 recorded incidents, compared to a total 26,496 for the previous year.

2006:
•    Growing sectarian violence and continuous anti-coalition attacks marked the beginning of 2006. Also, government creation talks took place.
•    The government of Iraq took office on May 20.
•    Coalition forces formally transferred control of a province to the Iraqi government, the first since the war.
•    Military prosecutors charged eight US Marines with the murders of 24 Iraqi civilians in Haditha.
•    Saddam Hussein was hanged on December 30, 2006 after being found guilty of crimes against humanity by an Iraqi court after a yearlong trial.

2007:
•    British Prime Minister Blair announced that afterOperation Sinbad British troops would begin to withdraw from Basra, handing security over to the Iraqis.
•    Danish Prime Minister Anders Fogh Rasmussen announced the withdrawal of 441 Danish troops from Iraq.
•    On August 14 the deadliest attack of the war occurred. Nearly 800 civilians were killed by suicide bomb attacks. US officials blamed al-Qaeda. The targeted villagers belonged to the non-Muslim Yazidi ethnic minority.
•    Entire neighborhoods in Baghdad were ethnically cleansed by Shia and Sunni militias and sectarian violence has broken out in every Iraqi city where there is a mixed population.

2008:
•    The ongoing conflict between Turkey and PKK intensified on February 21, when Turkey launched a ground attack into the Quandeel Mountains of Northern Iraq.

2009:
•    On January 1, the US handed control of the Green Zone and Saddam Hussein's presidential palace to the Iraqi government in a ceremonial move. The country's prime minister described this as a restoration of Iraq's sovereignty.
•    On January 31, Iraq held provincial elections. Provincial candidates faced some (attempted) political assassinations, and there was other violence related to the election.
•    US President Barack Obama announced in February that the US combat mission in Iraq would end by August 31, 2010.
•    The UK formally ended combat operations on April 30. Britain handed control of Basra to the United States Armed Forces.
•    The withdrawal of U.S. forces began at the end of June. On June 29, US forces withdrew from Baghdad.

Response of the international community
The US and its coalition invaded Iraq (among other goals) to remove Saddam Hussein from power and to give humanitarian aid. Since the beginning there has been much criticism on the invasion. According to a BBC poll in 25 countries, 73% of the global population disapproves of the US handling of the Iraq War. The UN Secretary-General Kofi Annan believes the invasion in Iraq was an illegal act that contravened the UN Charter.

Sources
•    Uppsala Conflict Database (http://www.pcr.uu.se/gpdatabase/gpcountry.php?id=77®ionSelect=10-Middle_East).
•    Joint Declaration by Russia, Germany and France on Iraq, France Diplomatie February 10, 2003( https://pastel.diplomatie.gouv.fr/editorial/actual/ael2/bulletin.gb.asp?liste=20030211.gb.html).
•    "Press Briefing by Ari Fleischer". Office of the Press Secretary. 2003-03-24. (http://georgewbush-whitehouse.archives.gov/news/releases/2003/03/20030324-4.html).
•    "Pentagon: Saddam is POW". CNN. 2004-01-10. (http://www.cnn.com/2004/WORLD/meast/01/09/sprj.nirq.saddam/).
•    Residents hang slain Americans' bodies from bridge – CNN.com (http://www.cnn.com/2004/WORLD/meast/03/31/iraq.main/)
•    Thomas E. Ricks (2006) Fiasco, The American Military Adventure In Iraq. Penguin (413-414)
•    8 Marines Charged With 24 Iraqi Slayings". FOX. 2006-12-22. (http://www.foxnews.com/wires/2006Dec22/0,4670,MarinesHaditha,00.html).
•    Saddam Hussein executed in Iraq". BBC. 2006-12-30. (http://news.bbc.co.uk/2/hi/middle_east/6218485.stm. Retrieved January 5, 2010).
•    BBC NEWS February 21, 2007, Blair announces Iraq troops cut (http://news.bbc.co.uk/2/hi/uk_news/politics/6380933.stm)
•    Sects slice up Iraq as US troops 'surge' misfires,  The Observer, Sunday 4 March 2007 (http://www.guardian.co.uk/world/2007/mar/04/usa.iraq)
•    Steven Lee Myers America’s Scorecard in Iraq February 7, 2009 New York Times (http://www.nytimes.com/2009/02/08/weekinreview/08myers.html
•    BBC: UK combat operations end in Iraq)  
•    World View of US Role Goes from Bad to Worse", BBC World Service. 2007-01-23. (http://news.bbc.co.uk/1/shared/bsp/hi/pdfs/23_01_07_us_poll.pdf)