The 2nd Battalion, 3rd Marines was originally activated on 1 May 1942 as the 3rd Training Battalion at New River, North Carolina.  Recruits from Parris Island soon brought the battalion up to authorized strength, and on 17 June 1942, it was redesignated to the 2nd Battalion, 3rd Marines.  The next few months were used to organize and train the Marines of the new battalion.  In August the 2nd Battalion, 3rd Marines was relocated to the West Coast and the following month it embarked on board the USS Lurline for the southwestern Pacific.  The battalion arrived at Tutuila, American Samoa, and joined the 2nd Marine Brigade.  For the next eight months, the 2nd Battalion, 3rd Marines participated in various land exercises and jungle warfare training to improve combat efficiency.  The next move for the battalion came in May 1943 when it was relocated to Auckland, New Zealand.  In August the 2nd Battalion, 3rd Marines was deployed on Guadalcanal.  After a more intense period of training, the battalion went into combat for the first time on
1 November 1943.

Elements of 2/3 were the first Marines to land near Cape Torokina, Empress Augusta Bay, for the Bougainville operation. For almost a month, 2/3 slowly advanced, fighting both the Japanese and the jungle.  Army units began replacing the Marines by the end of December and 2/3 was relocated to Guadalcanal.  Again, the battalion began a period of intensive jungle training for their next planned objective  Guam.

The first landings on Guam took place on 21 July 1944.  Extremely rugged terrain made progress slow after the 2nd Battalion, 3rd Marines waded ashore.  The greatest problem faced by the battalion was ferreting the Japanese out of the caves in which they were hiding.  On 10 August, the island was declared secure, but Japanese resistance continued sporadically for many months.

While on Guam, the 2nd Battalion, 3rd Marines was designated as part of the floating reserve for the Iwo Jima operation.  The battalion arrived off the coast of Iwo Jima on 27 February 1945, but returned to Guam a week later without ever landing.
Four months after the Japanese surrender, in August 1945, 2nd Battalion, 3rd Marines embarked
onboard the USS Hampton and sailed for San Diego.  On 31 December 1945, the battalion was deactivated at Camp Pendleton.

The 2nd Battalion, 3rd Marines was reactivated during the Korean War on 20 July 1951 at Camp Pendleton.  At first, the battalion was assigned to the 3rd Marine Brigade.  In January 1952, the designation was changed to the 3rd Marine Division.  While at Camp Pendleton, 2/3 participated in several exercises including TRAEX ALISO and DESERT ROCK V.  The entire 3rd Marine Division was deployed to Japan and the 2nd Battalion, 3rd Marines sailed for Camp Fuji.  Field and landing exercises continued for the battalion both in Japan and on Iwo Jima.

In March 1957, the battalion embarked on board the USS Bayfield and sailed from Yokosuka, Japan, for its new location, Camp Sukiran, Okinawa.  Again, the battalion participated in various 3rd Division exercises.  In November 1960, the 2nd Battalion, 3rd Marines sailed for Camp Pendleton, where it joined the 1st Marine Division.  The battalion remained at Camp Pendleton as part of the 1st Marine Division for more than a year and then returned to Camp Schwab, Okinawa, where it again rejoined the 3rd Marine Division.  For the next few years, 2/3 maintained its combat readiness on Okinawa and acted as the Battalion Landing Team of the Seventh Fleet at various times.

As Marine ground units began landing in Vietnam in early 1965, BLT 2/3 arrived off the coast of DaNang on board the USS Lenawee.   The battalion went ashore in April 1965 and immediately began combat operations in the DaNang area. In November 1965, 2/3 was rotated to Okinawa for a few weeks before boarding ship to become the Special Landing Force (SLF) of the Seventh Fleet.  While on board the USS Valley Forge, 2/3 participated in Operation DOUBLE EAGLE I.  At the end of February 1966, the battalion again landed in Vietnam, where it remained for a year before being designated SLF BRAVO. An amphibious assault/search and destroy operation, BEACON STAR, was conducted by 2/3 in Quang Tri Province in April 1967.  Hill 861 was taken by the 2nd and 3rd Battalions, 3rd Marines, with the aid of air strikes and artillery.  This operation was followed by many others, including BEAVER TRACK, BEAR CHAIN, and KANGAROO KICK.  After serving as the Special Landing Force, the 2nd Battalion, 3rd Marines returned to Quang Tri Province in early 1968.
For the next year and a half, the battalion conducted operations in the Khe Sanh and A Shau Valley areas.

President Nixon's plan for redeployment of American troops from Vietnam began in the summer of 1969. Units of the 3rd Marine Division were among the first to be withdrawn.  The 2nd Battalion, 3rd Marines was greatly reduced in strength before it was relocated in October 1969.  When the battalion arrived at Camp Pendleton, it joined the 5th Marine Expeditionary Brigade and was brought up to authorized strength.

Upon the return of the 1st Marine Division from Vietnam to Camp Pendleton, a realignment of units occurred.  Units organic to the 3rd Marine Division were eventually assigned to the 1st Marine Brigade in Hawaii.  Personnel were shifted to units of the 1st Division so they could be brought to authorized strength.  On 7 April 1971, the personnel of the 2nd Battalion, 3rd Marines were used to reform 2/7 at Camp Pendleton.  The 2nd Battalion, 3rd Marines sailed for Kaneohe Bay, were it joined the 1st Marine Brigade.

MARCH 1972