2008: Iraqi Forces Take the Lead

Basra
From March 25 to April 24, 2008, the Iraqi army and police, led by the Iraqi government, launched Operation Charge of the Knights against the Mahdi Army in Basra, supported by U.S. and British air power, advisers, and intelligence. The militia withdrew from the city. See Basra and Sadr City.
Sadr City
At the same time, militia fighters fired rockets from Baghdad's Sadr City at the Green Zone. U.S. and Iraqi forces fought in Sadr City through the spring and built a concrete barrier along al-Quds Street, beginning April 15. A ceasefire took effect on May 11, followed by an agreement allowing Iraqi forces to enter the district.
The agreements
In November 2008 the United States and Iraq signed the Status of Forces Agreement, which set deadlines for U.S. forces to leave Iraqi cities and then the country. The Iraqi Surge campaign ended on December 31, 2008.