Sept. 22, 1980 Border disputes between Iraq and neighboring Iran ascend into a full-scale war. In response to several military setbacks, Iraq is forced to withdraw from occupied portions of Iran by 1982.

March 16 1988 In an attempt to single out political dissenters, Hussein uses chemical weapons against Kurds at Halabja in Iraq, killing more than 5,000.

Aug. 29, 1988 With an estimated 1.5 million war casualties, Iran and Iraq accept a U.N.-mandated cease fire, ending hostilities between the two nations.

Aug. 2, 1990 Seeking to expand Iraq petroleum and land holdings, Hussein invades Kuwait in an attempt to annex the small oil-producing nation. In response, the United Nations demands a full withdrawal, imposing economic sanctions on Iraq.

Jan. 16, 1991 U.S. and coalition forces begin aerial bombing in Iraq, officially opening the war in the Gulf. Following the liberation of Kuwait in March, Iraq agrees to a cease-fire.

April 8, 1991 The United Nations sponsors a plan to set up a Kurdish safe-territory in northern Iraq, ending Iraqi military action in the region.

Oct. 31, 1998 The U.N. Special Commission to Oversee the Destruction of Iraq's Weapons of Mass Destruction (Unscom) program ends when Iraq evicts weapons inspectors, prompting the United States and allies to launch Operation Desert Fox in a coordinated effort to destroy Iraq's nuclear facilities.

November 2002 Following U.S. disarmament threats, Hussein allows weapons inspectors back into Iraq. By March of 2003 U.S. military intelligence indicates Hussein is hiding nuclear materials, prompting the final withdrawal of inspectors in preparation for an American invasion.

April 9, 2003 U.S. troops enter Baghdad, breaking Hussein's grip on the capital.

May 2003 President Bush announces an end to major combat operations on May 1; the United Nations lifts economic sanctions and approves a U.S.-led administration in Iraq.

July 2003 Saddam Hussein's sons, Uday and Qusay, are captured and killed in a firefight; the Bush-backed Iraqi Governing Council meets for the first time.

November 2003 More U.S. soldiers have been killed in Iraq during post-war military operations than during the war.

Dec. 14, 2003 Hussein is caught hiding near his hometown Tikrit, located in the Sunni Triangle.

February 2004 Suicide bombers kill at least 225 people in attacks on an army recruiting center, police station and offices of the two main Kurdish factions.

March 2004 The Iraqi Governing Council signs an interim constitution on March 8. Four suicide bombing attacks at Shiite Muslim shrines kill more than 180 people. At least 660 people have died from suicide bombings since the declared end of combat operations.

Jan. 30, 2005 Eight million people vote for a Transitional National Assembly-- the temporary Iraqi governing group. The Shiite United Iraqi Alliance and various Kurdish parties are voted into the majority, offsetting Sunni power in the region. In April, the assembly votes Kurdish leader Jalal Talabani as president and Shiite Ibrahim Jaafari as prime minister.

May 2005 Violence continues: Bombings, suicide attacks and shootings push the civilian death toll for the month to 672.

October 2005 Iraqi voters approve a new constitution, despite disagreements between the Shiite/Kurdish majority and Sunni minority over federalism and oil rights provisions included in the document.

October 2005 Nearly two years after his capture, Hussein appears in an Iraqi court on charges of crimes against humanity. Citing safety concerns, the trial is postponed until November.

Dec. 15, 2005 Iraqis head back to the polls for full-fledged democratic elections-- the first permanent elections in the country's history. In an effort to stall the vote, insurgent violence continues to escalate in the region with suicide bombings and the hostage-taking of several foreigners.

Jan. 20, 2006 Farid Ayar, spokesperson for the Independent Electoral Commission of Iraq, reports the Dec. 15 parliamentary election results: The Shiite Iraqi Alliance captures 128 of the 275 votes in the assembly, failing to win the two-third majority necessary to rule unopposed, thus forcing a partnership with Sunni and Kurdish political groups to form the new government.

Feb 23, 2006 Violence erupts in Samarra after insurgents bomb and damage the Shiite's revered golden-domed Askariya Shrine. In the days following, sectarian unrest and a string of suicide bombings plunge Iraq closer to civil war.

April 22, 2006 Following four months of political turmoil, President Talabani asks Jawad al-Maliki to help form a government as Iraq's new prime minister.

Dec. 29, 2006 Hussein is executed, 56 days after being sentenced to death for his role in the 1982 killings of 148 Shiite Muslims.

February 2007 President Bush deploys 21,500 additional combat troops to patrol the streets of Baghdad as increasing ethnic violence threatens to erupt into civil war. The "troop surge" is widely criticized in Congress, and anti-war legislators begin discussing plans for a complete U.S. pullout by 2008.

March 20, 2007 Four years have elapsed since the onset of the conflict; more than 3,000 U.S. troops and at least 60,000 Iraqi civilians are dead.

May 1, 2007 President Bush vetoes a bill including provisions that would set a timetable for U.S. combat troop withdrawal in Iraq and Afghanistan; Congress begins deliberations on a new war spending bill.

August 2007 Iraq's main Sunni political bloc withdraws from the cabinet. Shia and Kurdish leaders unite to support Prime Minister Maliki's government. Radical Shia cleric Muqtada al-Sadr suspends his Mahdi army militia's operations.

September 2007 Blackwater security guards, contracted by the US, are accused of unnecessarily firing upon and killing 17 Iraqi civilians.

March 2008 Levels of violence remain constant because of security gains by US troops. Five years after the start of the conflict, 4,000 US service members are dead and cost of the war reaches $600 billion .

August 2008 Amid negotiations of a security pact, Prime Minister Maliki demands a firm withdrawal date for all US troops. The conditional agreement set a soft deadline of 2011.