3D Combat Engineer Battalion was first formed on September 16, 1942 as 1st Battalion, 19th Marine Regiment in San Diego, California, and was assigned to the 3D Marine Division. During November of 1942 the battalion was relocated to Camp Pendleton, California. In February of 1943 the battalion was forward deployed to Auckland, New Zealand. They deployed out of Auckland numerous times, serving with distinction in the Bougainville, Guam, and Iwo Jima campaigns. On September 7, 1944 they were re-designated the 3D Engineer Battalion. Following the end of World War II the battalion was deactivated at Marine Corps Base Camp Pendleton, California on January 12, 1946.
The unit was reactivated on March 5, 1952 at Camp Pendleton, California, as the 3D Engineer Battalion and assigned to the 3D Marine Division. By the next year they were stationed in Kobe, Japan, and they relocated during February 1955 to Tengan, Okinawa. During January of 1956 they were once again relocated to Camp Kawasaki, Okinawa. On July 28, 1958 the battalion was redesignated as the 3D Pioneer Battalion, and soon after they were relocated to Camp Koza, Okinawa. In February of 1962 the battalion moved to Camp Hansen, Okinawa, where they were redsignated as the 3D Engineer Battalion on May 1, 1963.
The 3D Engineer Battalion deployed to Da Nang, Republic of Vietnam, in June 1965 and remained in Vietnam until April 1969. During this time the battalion operated from Da Nang, Dong Ha, Gia Le, Quang Tri, Cua Viet, Camp Carroll, Cam Lo, and Vandegrift Combat Base, earning recognition for its superior service. Soon after returning from deployment 3D Engineer Battalion was stationed in October 1969 to Camp Schwab, Okinawa, only to be relocated in November 1970 to Camp Hansen, Okinawa.
On May 15, 1976 the battalion was redesignated as the 3D Combat Engineer Battalion.
Three of 3D Combat Engineer Battalion’s companies deployed in support of Operations Desert Shield/Desert Storm between August 1990 and March 1991. One company deployed from Hawaii with the 1st Marine Expeditionary Brigade, another deployed via amphibious shipping August 15, 1990 from Okinawa, and the final company landed in Saudi Arabia five days before the air war began. The Marines from 3D CEB participated in the initial breaching operations during the ground war allowing coalition forces to rapidly advance through Iraqi controlled terrain. The battalion latter participated in Operation Sea Angel in Bangladesh during May 1991, and Operation Fiery Vigil in the Philippines during June of 1991.
In 1995, 3D Combat Engineer Battalion was deactivated, and its personnel were dispersed to other combat engineers units throughout the Marine Corps.
The reactivation of 3D Combat Engineer Battalion began on 1 October, 2007 when Alpha Company was activated at 29 Palms, CA. The company headquarters and two platoons deployed to Iraq in support of Operation Iraqi Freedom and fell under the command of Regimental Combat Team 5 during 2008. During that timeframe A Co, 2d Platoon was attached to 2nd Battalion, 7th Marines and deployed to Afghanistan in support of Operation Enduring Freedom.
3D Combat Engineer Battalion continued to grow with the activation of Bravo Company, Engineer Support Company, and the Headquarters and Service Company. 3D Combat Engineer Battalion’s first Commanding Officer, LtCol James H. Bain, will assume command of the battalion during a ceremony held on 21 August, 2009.