The 2d Combat Engineer Battalion was activated on 1 November 1940 in order to support 2d Marine Brigade. With existing Company A and the activation of the Headquarters and Service Company, Companies B and C were organized 6 December 1940 in San Diego, California. On 1 April 1941, the Engineers were assigned to Division Special Troops of the 2d Marine Division. On 4 November 1941, 2d Engineer Battalion was relocated to Marine Barracks, Navy Yard, Pearl Harbor, Hawaii. Upon Arrival, Headquarters and Service Company and Company A were assigned to Construct Camp Caitlin, Oahu.
The 2d Engineer Battalion was relocated on 13 May 1942 to Camp Elliot, San Diego. From here, Engineers from Company A embarked for Guadalcanal, and participated in the landing on that island. On 8 September 1942 2d Engineer Battalion was redesignated as First Battalion, 18th Marines. During World War II, the Engineers of 18th Marines participated in Campaigns on Guadalcanal, Tarawa, Saipan, Tinian, and Okinawa. 18th Marines was redesignated 16 August 1944 as the 2d Engineer Battalion. On 23 September 1945, 2d Engineer Battalion was redeployed to Nagasaki, Japan to begin it's duty as on Occupational Force.
The 2d Engineer Battalion relocated to Camp Lejeune, during July 1946. A major redesignation took place on 17 May 1958 with 2d Engineer Battalion becoming the 2d Pioneer Battalion, 2d Marine Division. Engineers with BLT's 1/8, 3/6, and 2/2 landed in Lebanon during the summer of 1958. The 2d Pioneer Battalion maintained a combat-ready posture during the October/November Cuban Missile Crisis while on maneuvers in the Caribbean. Another change of designation took place on 1 April 1976 when the 2d Pioneer Battalion returned to it's former designation as the 2d Engineer Battalion. During the spring of 1965, Marines from 2d Engineer Battalion landed in the Dominican Republic on a peace keeping mission. Also, training exercises in numerous European and South American Countries were supported by Marines from 2d Engineer Battalion, who participated in civic action projects. On 15 April 1976 the 2nd Engineer Battalion was designated as 2d Combat Engineer Battalion.
In the 1970's and early 1980's the Battalion furnished Combat Engineer Support to the Battalion Landing Teams (BLT) in the Mediterranean, the Caribbean, 29 Palms, Norway, and Guantanamo Bay, Cuba. From August 1982 to February 1984 Marines from 2d Combat Engineer Battalion were part of the multinational peacekeeping force in Beirut, Lebanon. Late in October 1983, Combat Engineers landed and occupied the island of Grenada with the 22nd Marine Amphibious Unit. The Battalion continued to provide Combat Engineer Platoons to the BLT's of the 22nd and 26th Marine Expeditionary Units and support elements of the Division throughout the world. During April 1990, elements of the Battalion supported Division units attached to Marine Forces Panama and participated in Operation "Just Cause". In August 1990, Company D, while deployed aboard the USS Barstable County off the coast of West Africa participated in Operation "Sharp Edge" assisting in the evacuation of civilians from Liberia. During Operations Desert Shield/Storm the Battalion deployed in support of the 4th MEB and the 2d Marine Division leading the Division through the myriad of obstacle belts into Kuwait. Recently engineers have participated in military operations in Bosnia, Haiti, and Cuba, and most recently, participating in Operation Enduring Freedom and Operation Iraqi Freedom.