In October 2005, the secretary of defense directed the formation of a Marine component of U.S. Special Operations Command. It was determined the Marine Corps would initially form a unit of approximately 2,500 to serve with USSOCOM.
On Feb. 24, 2006 MARSOC activated at Camp Lejeune, N.C. MARSOC initially consisted of a small staff and the Foreign Military Training Unit, which had been formed to conduct foreign internal defense. FMTU was then designated as the Marine Special Operations Advisor Group.
In the months after the activation of MARSOC, the structure and personnel of both 1st and 2d Force Reconnaissance Company transferred to MARSOC to form 1st and 2d Marine Special Operations Battalions.
In April of 2009, MSOAG was re-designated as the Marine Special Operations Regiment with the 1st, 2d, and 3d MSOBs as subordinate units. The newly designated 3d MSOB incorporated the structure and personnel from MSOAG's former companies.
MARSOC also formed the Marine Special Operations Support Group and the Marine Special Operations School. The MSOSG provides combat support and combat service support to MARSOC units, to include: logistics, communication and intelligence. The MSOS screens, assesses, selects and trains Marine Special Operations Forces and is responsible for developing doctrine.
As a service component of USSOCOM, MARSOC is tasked by the commander of USSOCOM to train, organize, equip and when directed by commander of USSOCOM, deploy task organized, scalable and responsive U.S. Marine Corps Special Operations Forces worldwide in support of combatant commanders and other agencies. MARSOC has been directed to conduct foreign internal defense, special reconnaissance, and direct action. Commander, USSOCOM assigns MARSOC missions based on USSOCOM priorities. MARSOC units then deploy under USSOCOM deployment orders.
MARSOC deployed its first units in August 2006, six months after initial activation. Since then, MARSOC has continuously deployed. MARSOC’s current deployments include Marine Special Operations Teams conducting foreign internal defense and Marine Special Operations Companies from the Marine Special Operations Battalions conducting foreign internal defense, special reconnaissance and direct action.