2003
August: Four months after the fall of Saddam Hussein, a car bomb kills leading Shi'ite politician Ayatullah Mohammed Bakir al-Hakim and 90 others near Najaf's Tomb of Ali
2004
January: A letter found in the possession of a captured al-Qaeda operative details Abu Mousab al-Zarqawi's ambitions to provoke Shi'ites and start a civil war in Iraq
March: More than 180 Shi'ites in Karbala and Baghdad are killed in suicide bombings
April: Supporters of Shi'ite cleric Muqtada al-Sadr stage an uprising against U.S. troops in several Iraqi cities
August: Pro-Sadr forces clash with the U.S. in Baghdad and Najaf. After the intervention of Grand Ayatullah Ali Husaini Sistani, the rebels agree to end their insurgency
December: More than 60 Shi'ites are killed in bombings in the holy Shi'ite cities of Najaf and Karbala
2005
January: In multiparty elections, Shi'ites and Kurds turn out, but most Sunnis boycott the polls. A coalition of Shi'ite religious parties wins a majority
November: U.S. troops discover 173 prisoners, mostly Sunnis, some bearing signs of torture, held in a government-run bunker
December: The Shi'ite alliance wins the most seats in national elections but not enough to govern without Sunni participation
2006
February 22, 2006: The bombing of a sacred Shi'ite shrine in Samarra sparks sectarian violence that leaves more than 200 dead, including a group of foreign Arab prisoners in Basra