Headquartered at Marine Corps Base Camp Pendleton, Calif., 1st Marine Division is a multi-role, expeditionary ground combat force. The Division is employed as the ground combat element of I Marine Expeditionary Force or may provide task-organized forces for assault operations and such operations as may be directed. The 1st Marine Division provides amphibious forcible entry capability to the naval expeditionary force and conducts subsequent land operations in any environment.
The Division provides fully-trained units and personnel in support of Operation Enduring Freedom, Marine Expeditionary Units, and the Unit Deployment Program to Okinawa, Japan.
Headquarters Battalion provides command and administration for 1st Marine Division. Within the Battalion are Headquarters and Service Company, Communications Company, and Truck Company. The Division headquarters is located at mainside, while Headquarters Battalion and its companies are located at Camp Margarita.
Infantry: 1st, 5th and 7th Marine Regiments
The 1st, 5th and 7th Marine Regiments each consist of one headquarters company and four infantry battalions, with one battalion deployed outside the continental United States at all times. The infantry battalions are the basic tactical units the regiment uses to accomplish its mission of locating, closing with and destroying the enemy by fire and maneuver. The 1st and 5th Marines are located at Camp Horno and Camp San Mateo, respectively. The 7th Marines are located at Marine Corps Air Ground Combat Center Twentynine Palms, Calif.
Artillery: 11th Marine Regiment
The 11th Marine Regiment consists of a headquarters battery and four artillery battalions. The regiment is the primary source of fire support for 1st Marine Division. It provides direct and indirect fire support to frontline units as required by the infantry commanders. The regiment's organic weapons are the 155 mm M777 lightweight howitzer, the High Mobility Artillery Rocket System (HIMARS) and the 120 mm Expeditionary Fire Support System. The regiment is headquartered at Camp Las Pulgas. Camp Las Flores houses 5th Battalion, while 3rd Battalion resides at Marine Corps Air Ground Combat Center Twentynine Palms, Calif.
1st Tank Battalion
The 1st Tank Battalion was activated on Nov. 1, 1941, and is located at Marine Corps Air Ground Combat Center Twentynine Palms, Calif. Its mission is to provide combat power to 1st Marine Division in the form of amphibious and Maritime Preposition Forces and conduct operations ashore utilizing maneuver, armor protected firepower, and shock action in order to close with and destroy the enemy. As a separate battalion, 1st Tank Battalion is responsible for providing armored assets as well as anti-armor systems and staff expertise in their employment. The battalion is equipped with the M1A1 Abrams Battle Tank.
1st and 3rd Combat Engineer Battalions
The 1st and 3rd Combat Engineer Battalion provide both tactical and logistical engineer support to 1st Marine Division, as well as maneuver forces as required. Camp San Mateo houses 1st CEB, while 3rd CEB is headquartered at Marine Corps Air Ground Combat Center Twentynine Palms, Calif.
3rd Assault Amphibian Battalion
The mission of 3rd Assault Amphibian Battalion is to transport the surface assault elements of the landing force from amphibious shipping to inland objectives during the amphibious assault and to provide support to mechanized operations ashore. The amphibious assault vehicles are primarily used to transport personnel in tactical operations. The battalion is located at Camp Del Mar.
1st and 3rd Light Armored Reconnaissance Battalions
The Division has two light armored reconnaissance battalions. The mission of the light armored reconnaissance battalion is to conduct reconnaissance, security and economy of force operations, and within its capabilities, limited offensive or delaying operations that exploit the unit's mobility and firepower. The 1st Light Armored Reconnaissance Battalion was activated May 31, 1985, and is located at Camp Las Flores. The 3rd Light Armored Reconnaissance Battalion was activated on Sept. 11, 1986, and is located at Marine Corps Air Ground Combat Center Twentynine Palms, Calif.
1st Reconnaissance Battalion
The 1st Reconnaissance Battalion was originally activated on 1 March 1937. The Division reactivated the battalion on June 8, 2000. Before 1944, Marine reconnaissance consisted primarily of scout sniper units. In April 1944, a two-company amphibious reconnaissance battalion was formed with the mission of conducting beach reconnaissance and hydrographic survey. Today, the battalion performs a wide variety of tactical and special operations in support of the Division. The battalion is headquartered at Camp Las Flores.