Iraq War order of battle, 2009

Below is an estimated list of the major units deployed within the Multi-National Force – Iraq and other United States military units that were operating in Iraq under the U.S. Central Command (USCENTCOM) in 2009, during the Iraq War.
In military science terminology, the description of the units involved in an operation is known as the order of battle (ORBAT). NATO and the U.S. Department of Defense define the order of battle as the identification, strength, command structure, and disposition of the personnel, units, and equipment of any military force.
From September 2008 to 31 December 2009, the overall military commander in Iraq was General Raymond T. Odierno, Commander, Multi-National Force - Iraq (MNF-I) who reported to United States Central Command. MNF-I replaced Combined Joint Task Force 7 in May 2004. MNF-I consisted of Multi-National Corps - Iraq, Multi-National Security Transition Command - Iraq (MNSTC-I), and the Joint Contracting Command, Iraq/Afghanistan (JCCIA).
On January 1, 2010, Multi-National Force Iraq became United States Forces - Iraq.
Special Operations Task Forces.
There is a distinction in U.S. military terms between the troops of Multinational Force-Iraq and forces which fall directly under CENTCOM's control but are in Iraq also. There are two special operations task forces operating in Iraq, Task Force 77 and CJSOTF-AP. Though TF 77, a 'black' force, does not answer to MNF-Iraq, it is included here for the sake of completeness of the U.S. forces operating within Iraq. TF 77 was under the command of the Joint Special Operations Command and its principal mission was to hunt down the leaders of al-Qaeda in Iraq (AQI).
The second force, which appears to be separate from TF 77, is the Combined Joint Special Operations Task Force-Arabian Peninsula (CJSOTF-AP). CJSOTF-AP is a "white", or unclassified, special operations task force that as of 2008 was always organized around the headquarters of either 5th Special Forces Group or 10th Special Forces Group. Combined Joint Special Operations Task Force-Arabian Peninsula (CJSOTF-AP), itself answers to Special Operations Command Central.
Order of battle as of 2009.
Unless otherwise noted, all units were U.S. in origin. This order of battle extends to battalion level and lists maneuver units only; artillery, support, special operations, and advisory units are not listed. Many brigade combat teams (BCTs) lent battalions to other BCTs during the course of their deployments, giving them "operational control" of those units. In such cases, the battalion's name is followed by "OPCON." Many higher-echelon units have two or more designations, often the formal unit around which the formation is based and then the name of the provisional task force; in these cases, both names are included, separated by a slash. Units were stationed at a variety of bases, including Forward Operating Bases (FOB), Contingency Operating Bases (COB) and Joint Security Stations (JSS).
Multi-National Corps - Iraq.
(General Raymond Odierno)—Camp Victory, Baghdad
Multi-National Division Baghdad.
1st Cavalry Division (Major General Daniel P. Bolger)—Camp Victory, Baghdad
Also known as Task Force Baghdad, this division headquarters was provided by the 1st Cavalry Division. The division's area of responsibility (AOR) was the city of Baghdad. MND-B headquarters was previously provided by Headquarters 1st Armored Division (2003–2004), Headquarters 1st Cavalry Division (2004), Headquarters 3rd Infantry Division (2004–2005), Headquarters 4th Infantry Division (2005-2006) and Headquarters 1st Cavalry Division (2006-2007), Headquarters 4th Infantry Division (2007-2009), Headquarters 1st Cavalry Division (2009-2010).
Multi-National Division South.
34th Infantry Division - (Major General Rick C. Nash)—Contingency Operating Base Basra 
Multi-National Division South, also known as Task Force Mountain, assisted the Iraqi Armed Forces with security in the area south of Baghdad ranging from Najaf to Wasit provinces extending to Basra. MND-South headquarters was provided by the 10th Mountain Division (Light) from Fort Drum, New York. The areas south of Baghdad were previously organized into Multi-National Division-Center, under U.S. leadership, and Multi-National Division (South East), which was provided by the British Army. The areas were merged into MND-South on March 31, 2009, to reflect the departure of the UK from Iraq. MND-Center took in portions of the area previously controlled by the long-disbanded Polish-led Multi-National Division Central-South.
The 34th Division transferred control of MND/USD-South to the 1st Infantry Division on February 2, 2010.
Multi-National Division North.
25th Infantry Division/TF Lightning (Major General Robert L. Caslen Jr.)—COB Speicher, Tikrit
This division headquarters was provided by the 25th Infantry Division and was also known as Task Force Lightning. Its area of responsibility included the cities of Balad, Kirkuk, Tikrit, Mosul, and Samarra. It was based at Contingency Operating Base Speicher outside Tikrit, where one of its brigades was also stationed. It also had one brigade based in Mosul, one in Kirkuk, one at Taji, and one in Baqubah.
Multi-National Force West.
II Marine Expeditionary Force (Forward) (Major General Richard T. Tryon) — Al Asad Airbase
This formation headquarters was provided by the II Marine Expeditionary Force (Forward). It covered western Iraq, including Al Anbar Governorate and the cities of Ramadi and Fallujah, the area where Iraq's Sunni insurgency was at its strongest. Headquartered first at Camp Fallujah and then at Al Asad Airbase.
3rd Sustainment Command (Expeditionary).
The 3rd Sustainment Command (Expeditionary) was the senior logistics command under Multi-National Corps-Iraq in support of Operation Iraqi Freedom 08-10. Its headquarters was located at Joint Base Balad.
Located approximately 40 miles north of Baghdad, Joint Base Balad was home to the headquarters of the U.S. Air Force's 332nd Air Expeditionary Wing. It was formerly known as Logistics Support Area Anaconda, the largest army supply center in Iraq.
Training.
Multi-National Security Transition Command - Iraq also played an important role.
United States naval forces in Iraq.
The U.S. Navy Riverine Squadrons of the U.S. Navy are elements of the Navy Expeditionary Combat Command (NECC) that have taken active part in the land operations in support of the army and Marine units. According to the Navy: "The Navy's Riverine force focuses on conducting Maritime Security Operations and Theater Security Cooperation in a riverine area of operations or other suitable area. The force is capable of combating enemy riverine forces by applying fires directly, or by coordinating supporting fires. It will share battle space with the other Services in an effort to close the seams in Doctrine, Tactics, Techniques, and Procedures, and Command, Control, Communications, Computers, Intelligence, Surveillance and Reconnaissance."
As of 2008, three riverine squadrons were active in the U.S. Navy, all under the command of Riverine Group 1, located in Norfolk, Virginia. Riverine Squadron 1 (RIVRON 1) deployed to Iraq in April 2007 and was relieved by Riverine Squadron 2 (RIVRON 2) in October 2007. Riverine Squadron 3 (RIVRON 3) was established in July 2007 and will presumably relieve RIVRON 2 in Iraq when their deployment is completed. Also deployed to Iraq, but in support of CJSOTF-AP and TF-77, is Combat Camera Group Pacific/Atlantic. This unit provides highly trained combat photographers who integrate with SEAL Teams and Special Forces Operational Detachment-Alpha (ODA) Teams in order to provide intelligence collection and combat documentation.
Other countries contributing to MNF-I.
United Kingdom.
The British Armed Forces was the second-largest contributor of foreign troops to Iraq, behind the United States. The British Army commanded the former Multi-National Division (South-East) (Iraq), which included UK, Italian, Australian, Romanian, Danish, Portuguese, Czech, and Lithuanian troops. However, the UK turned over command to the United States on March 31, 2009, and were in the process of withdrawing the 4,100 UK personnel based in and around Basra, leaving behind just 400 by the end of July 2009. 20th Armoured Brigade commanded the British forces in Iraq, which were then attached the U.S.-led Multi-National Division South.
Australia.
The Australian Defence Force had about 100 personnel providing security for the Australian Embassy in Baghdad. Known as Joint Task Force 633, it consisted mainly of infantry, cavalry, military police and combat service support personnel from the Darwin-based 5th Battalion, the Royal Australian Regiment and 2nd Cavalry Regiment. The ADF also had 45 personnel embedded in various coalition headquarters and contributes two officers to the United Nations Assistance Mission for Iraq (UNAMI).
Romania.
The Romanian Army had one battalion deployed to Iraq. The 26th Infantry Battalion, based at Contingency Operating Base Adder, part of Tallil Air Base, near Nasiriyah, was attached to the 4th BCT, 1st Cavalry Division and performed convoy and infrastructure guard missions. The battalion was withdrawn from early June 2009.
NATO Training Mission – Iraq.
The NATO Training Mission – Iraq was not a combat mission but was focused on training and mentoring the Iraqi Armed Forces and the Iraqi Police. It was supported and funded by all 28 NATO nations, and 14 nations had staff in theater as of January 2009, including Bulgaria, Denmark, Estonia, Hungary, Italy, Lithuania, Netherlands, Poland, Romania, Slovenia, Turkey, the United Kingdom, and the United States. Ukraine participated alongside these nations, though it is not a member of NATO.