In January 1942, the Commandant of the Marine Corps issued orders to form the 1st Separate Battalion, under the command of LtCol Merritt Edson. The mission of the Separate Battalion was to be a light force capable of spearheading amphibious invasions, conducting direct action raids, and fighting as a guerilla force behind enemy lines. Their organization and training were based on the experiences of the British Commandos, as well as the personal observations of Edson in his battles with Nicaraguan guerillas and another officer, Major Evans Carlson’s observations of the Chinese guerilla battles against the Japanese. The Second Separate Battalion, under Major Carlson, was formed in early February 1942.
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