Feb. 18 1999: Mohammed Sadek al-Sadr, Moqtada al-Sadr's father, killed near Najaf. Supporters in three cities rise against Saddam Hussein's regime; 200 are killed.
April 7, 2003: Moqtada al-Sadr emerges as key leader. Supporters in Baghdad's Saddam City seize weapons, rename area Sadr City.
April 9: Baghdad falls to coalition forces.
April 11: Mr. Sadr holds first Friday sermon in Kufa. Pro-US cleric Abdel Majid al-Khoei murdered in Najaf; US later accuses Sadr of arranging the murder.
July: Sadr militias fight with moderate Shiites to control Shrine of Ali in Najaf. Shootout with marines in Karbala leaves nine Iraqis dead.
August: Pro-Sadr riots break out in Sadr City, Sammara, and Basra. Sadr announces formation of the Mahdi army.
March 28, 2004: Sadr newspaper Al Hawza shut for anti-US rhetoric, sparking protests.
April 2: Sadr aide Mustapha Yacoubi arrested by US forces; pro-Sadr rallies turn violent.
April 4: Militias take control of Kufa, Karbala, Najaf, al-Kut, and Sadr City.
April 5: US issues warrant for Sadr arrest.
April 23: Rebellion loses steam; forces hold only Najaf, Sadr City. Sadr threatens US with suicide attacks if it enters Najaf to arrest him.