Includes 103 photos, maps and illustrations The following account represents one of the earliest efforts to chronicle Marine Corps operations in Iraq between 2004 and 2005. This was a significant period in the history of Operation Iraqi Freedom, seeing two battles fought over the city of Fallujah, the eruption of the Sadr revolt in an-Najaf, continuous counterinsurgency operations throughout Iraq, and initial efforts on the part of Marines to cultivate and forge alliances with the tribes of Iraq’s al-Anbar Province. Almost as soon as Saddam Hussein’s regime collapsed in 2003, it became apparent to U.S. commanders that a second deployment of Marines to Iraq would be necessary to conduct security and stability operations. This monograph recounts the first two years of this second deployment during which Marines were responsible for Iraq’s vast al-Anbar Province. This study focuses on I Marine Expeditionary Force’s deployment in 2004 and II Marine Expeditionary Force’s deployment of 2005, paying close attention to planning, counterinsurgency operations, and efforts to build civil-military relations with the Iraqi population. Particular attention is also paid to the first and second battles of Fallujah and the battle of an-Najaf.