The Regiment was authorized on April 23, 1775 in the Massachusetts State Troops as Cotton’s Regiment. Organized in spring 1775 at Roxbury to consist of ten companies from southern Plymouth County. Adopted on June 14, 1775 into the Continental Army and assigned to the Main Continental Army. It was assigned on July 22, 1775 to Thomas’ Brigade, an element of the Main Continental Army. Consolidated (less Mayhew’s, Wood’s, Benson’s and Bradford’s Companies) on January 1, 1776 with Bailey’s Regiment and consolidated unit re-designated as the 23rd Continental Regiment; concurrently, Mayhew’s Company reorganized and re-designated as Mayhew’s Company, 25th Continental Regiment, Wood’s Company reorganized and re-designated as Wood’s Company, 3rd Continental Regiment, and Benson’s and Bradford’s Companies consolidated and re-designated as Clap’s Company, 21st Continental Regiment.