U.S. 1st Marine Division

1st Marine Division
1st Marine Division insignia
Active	Active 1 February 1941 – present.
Allegiance	United States of America
Branch	United States Marine Corps
Type	Marine ground combat element forces
Role	Command and control organization containing four Marine regiments and several separate combat support battalions
Size	Marine Division (Approximately 22,000)
Part of	I Marine Expeditionary Force
Garrison/HQ	Marine Corps Base Camp Pendleton
Nickname(s)	The Old Breed Blue Diamond
Motto(s)	No Better Friend, No Worse Enemy
March	"Waltzing Matilda"
Engagements	Banana Wars Occupation of Veracruz, Mexico (1914) Occupation of Haiti (1915–1934) Occupation of the Dominican Republic (1916–24) Occupation of Cuba (1917–22) World War II Guadalcanal Campaign Battle of Cape Gloucester Battle of Peleliu Battle of Okinawa Korean War Battle of Pusan Perimeter Battle of Inchon Second Battle of Seoul Battle of Chosin Reservoir First and Second Battles of Wonju Battle of the Punchbowl Cold War Cuban Missile Crisis Vietnam War Operation Starlite Operation Piranha Operation Hastings Operation Union Operation Union II Operation Swift Operation Allen Brook Tet Offensive Gulf War Battle of Khafji Battle of Kuwait International Airport Liberation of Kuwait Somali Civil War Operation Restore Hope Iraq War Invasion of Iraq Battle of Baghdad First Battle of Fallujah Second Battle of Fallujah War in Afghanistan (2001–14) Helmand province campaign Operation Strike of the Sword Operation Moshtarak
Commanders
Current commander	MajGen Daniel J. O'Donohue
Notable commanders	Holland Smith Alexander Vandegrift William H. Rupertus Oliver P. Smith James M. Masters, Sr. Edwin A. Pollock James Mattis Pedro Del Valle

Banana Wars

World War II

Korean War

Cold War

Vietnam War

Gulf War

Somali Civil War

Iraq War

War in Afghanistan (2001–14)

The 1st Marine Division (1st MARDIV) is a Marine infantry division of the United States Marine Corps headquartered at Marine Corps Base Camp Pendleton, California. It is the ground combat element of the I Marine Expeditionary Force (I MEF).

It is the oldest and largest active duty division in the United States Marine Corps, representing a combat-ready force of more than 19,000 men and women. It is one of three active duty divisions in the Marine Corps today and is a multi-role, expeditionary ground combat force. It is nicknamed "The Old Breed".

The division is employed as the ground combat element (GCE) of the I Marine Expeditionary Force or may provide task-organized forces for assault operations and such operations as may be directed. The 1st Marine Division must be able to provide the ground amphibious forcible entry capability to the naval expeditionary force (NEF) and to conduct subsequent land operations in any operational environment.

The 1st Marine Division is currently organized around four regiments:

The lineal forebearer of the 1st Marine Division is the 1st Advanced Base Brigade, which was activated on 23 December 1913 at Philadelphia, Pennsylvania. (Subsequently, the brigade was redesignated as the 1st Brigade, and on 16 September 1935, as the 1st Marine Brigade). The brigade consisted of the Fixed Defense Regiment and the Mobile Defense Regiment, later designated as the 1st and 2nd Regiments, 1st Brigade, respectively. In 1916, while deployed in Haiti, the two regiments were again redesignated, exchanging numerals, to then become the 2nd and 1st Regiments, 1st Brigade. Between April 1914 and August 1934, elements of the 1st Brigade participated in operations in Mexico, Haiti, the Dominican Republic, and Cuba, receiving campaign credit for service in each nation. While the 1st Brigade did not serve ashore in the European theater during the First World War, the brigade was awarded the World War I Victory Medal Streamer, with one bronze star, in recognition of the brigade's service during that conflict. On 16 September 1935, the brigade was redesignated as the 1st Marine Brigade and deployed to Guantanamo Bay, Cuba in October 1940.