About

Who We Are

The 1st Marine Division is the oldest, largest and most decorated Marine division. Headquartered at Camp Pendleton, California, the Division is a force of 20,000 men and women organized to conduct combat operations. The 1st Marine Division is an adaptable expeditionary force in readiness; generating, deploying and returning forces in support of global force management. The Division stands ready to conduct contingency response requirements and is prepared to deploy as a scalable ground combat element to defeat peer, near-peer and hybrid threats across the range of military operations.

The First Marine Division

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 Marine Rotational Force - Darwin, Marine Expeditionary Units, and the Unit Deployment Program to Okinawa, Japan.

Headquarters Battalion

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 Combat Engineer Battalion

The 1st Combat Engineer Battalion provides both tactical and logistical engineer support to 1st Marine Division, as well as maneuver forces as required. 1st CEB is headquartered at Camp San Mateo.

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.

Overview

1st Marine Division was activated aboard the battleship USS Texas on February 1, 1941. It is the oldest, largest and most decorated division in the United States Marine Corps. The Division is comprised of Headquarters Battalion, 1st, 5th, 7th, and 11th Marine Regiments, 1st Reconnaissance Battalion, 1st and 3rd Light Armored Reconnaissance Battalions, 1st Combat Engineer Battalion and 3rd Assault Amphibian Battalion. These units represent a combat-ready force of more than 20,000 Marines and Sailors.

FORMING THE REGIMENTS

Division regiments were in existence as early as March 8, 1911, when the 1st Marine Regiment was formed at Guantanamo Bay, Cuba. The Marines saw action in Haiti in 1915, the Dominican Republic in 1916, and throughout the Caribbean during World War I. The 5th Marine Regiment was established on July 13, 1914, in Veracruz, Mexico. In 1925, they served in Santo Domingo, Dominican Republic, and participated in 15 major engagements during World War I. These include Belleau Wood, Chateau -Thierry and St. Mihiel. On August 14, 1917, 7th Marine Regiment was activated in Philadelphia. It spent the duration of World War I in Cuba and was disbanded after the war. It was reactivated in 1941. 11th Marines was formed in January 1918 in Quantico, Va., as a light artillery regiment. The Regiment went to France as an infantry unit, providing a machine gun company and a guard company. Decommissioned and reactivated twice between world wars, the Regiment again served as infantry in Nicaragua. Re-formed in 1940 as a full-fledged artillery unit, 11th Marines joined 1st Marine Division.

WORLD WAR II IN THE PACIFIC

Guadalcanal was the first major American Pacific campaign in World War II and the first time 1st Marine Division conducted combat operations as a division. The Division's actions during this operation won it the first of three Presidential Unit Citations during the war. The battles of Peleliu and Okinawa culminated in additional citations. Three weeks after Japan surrendered, the Division was dispatched to North China for occupation duty.

KOREAN WAR

When war broke out in Korea, 1st Marine Division provided support as the Pusan Fire Brigade and later landed in Inchon during the largest amphibious operation conducted at that time on September 15, 1950. The Division, as part of the U.S. Army X Corps, subsequently pushed back enemy forces north into mountains around the Chosin Reservoir before being surrounded by Chinese forces, who suffered more than 40,000 casualties trying to stop the Marines' withdrawal from the reservoir. This battle, including actions between April and September, earned the Division three Presidential Unit Citations.

CUBAN MISSILE CRISIS

In 1962, 2nd Battalion, 1st Marine Regiment, deployed to Guantanamo Bay for two months during the Cuban Missile Crisis. More than 11,000 Marines of the 5th Marine Expeditionary Brigade participated in the naval blockade, which forced the withdrawal of the missiles from Cuba.

VIETNAM

In 1965, 7th Marine Regiment participated in the first major engagements for American ground troops in South Vietnam. In March 1966, 1st Marine Division Headquarters was established at Chu Lai. By June, the entire Division was in South Vietnam. Its zone of operation included the southern two provinces of I Corps, Quang Tin and Quang Ngai.

Between March 1966 and May 1967, the Division conducted 44 named and unnamed operations. Major engagements included Operations Hastings and Union I and II. During the 1968 Tet Offensive, the Division was involved in fierce fighting with both Viet Cong and North Vietnamese Army elements. It successfully defended every enemy assault in its area of operations, pursuing the enemy back to their strongholds. It was during this period that the Division earned its seventh and eighth Presidential Unit Citations.

After six years, 1st Marine Division returned to California in 1971. In 1975, the Division supported the evacuation of Saigon by providing food and temporary shelter at Camp Pendleton for Vietnamese refugees as they arrived in the United States.

OPERATIONS DESERT SHIELD AND DESERT STORM

In 1990, 1st Marine Division formed the core of the force sent to Southwest Asia in response to Iraq’s invasion of Kuwait. During Operation Desert Shield, the Division provided the ground combat element of I Marine Expeditionary Force in Saudi Arabia. In 1991, the Division fought alongside 2nd Marine Division and the rest of the coalition forces in Operation Desert Storm. In 100 hours of offensive ground combat, 1st Marine Division destroyed the enemy in its path as it led the breakthrough to Kuwait City.

DISASTER RELIEF AND SOMALIA

Immediately following the Persian Gulf War, the Division sent units to assist in disaster relief efforts in Bangladesh through Operation Sea Angel and the Philippines through Operation Fiery Vigil. In 1992, 2nd Battalion, 9th Marine Regiment and the 15th Marine Expeditionary Unit brought relief to famine-stricken Somalia. The final phase of the operation involved the transition to a United Nations peacekeeping force. U.S. Marine involvement in Operation Restore Hope officially ended April 27, 1993, when the humanitarian relief sector of Mogadishu was handed over to Pakistani forces. Elements of the Division participated in the extraction of U.N. forces from Somalia.

OPERATION IRAQI FREEDOM

In early 2003, the Division deployed by air and sea to link up with its advanced headquarters deployed to Kuwait under I Marine Expeditionary Force. In a high-speed attack, and in conjunction with 1st (UK) Armoured Division and the U.S. Army 3rd Infantry Division, 1st Marine Division conducted the longest ground march in Marine Corps history.

The Division attacked to Baghdad alongside the U.S. Army and seized Saddam Hussein’s hometown of Tikrit. Afterward, the Division conducted stability operations in Baghdad, Tikrit and south-central Iraq from May to October 2003. These actions earned the Division its ninth Presidential Unit Citation.

In March 2004, 1st Marine Division relieved the 82nd Airborne Division in Iraq’s Sunni Triangle. During Operation Iraqi Freedom II, the Division conducted counter-insurgency operations throughout the Al Anbar Province, culminating in Operation Al Fajr, which liberated the insurgent stronghold of Fallujah and enabled the first legitimate elections to occur in Iraq. During February and March 2005, 1st and 2nd Marine Divisions successfully conducted the largest relief in place in the history of the Marine Corps. In 2006, 1st Marine Division once again deployed to Iraq as the ground combat element for I Marine Expeditionary Force.

OPERATION ENDURING FREEDOM

Throughout the course of the war, 1st Marine Division personnel and units deployed to Afghanistan to provide both advisory support and maneuver elements. In 2010, 1st Marine Division (Forward) deployed to Helmand province, Afghanistan, as part of the surge of more than 30,000 troops into the country. While in Afghanistan, the Division served as the ground combat element for Task Force Leatherneck, leading a multinational coalition and working alongside Afghan National Security Forces. While in Afghanistan, the Division served as the ground combat element for Task Force Leatherneck, leading a multinational coalition and working alongside Afghan National Security Forces. They conducted large-scale offensive operations throughout Helmand province, including Sangin and Musa Qaleh districts.

CURRENT OPERATIONS

Today, the Blue Diamond continues to provide fully trained and equipped, combat-ready formations in support of Global Force Management requirements deploying as part of the MEUs, UDPs and Marine Rotational Forces. Simultaneously, the Division maintains warfighting readiness through several annual exercises such as Steel Knight and Freedom Shield while also advancing modernization efforts for the Service through experimentation with new formations, equipment and technology.