Exercises, Naval Militia Camp, Somersville, New York, 1918. A naval militia in the United States is a reserve military organization administered under the authority of a state government. It is often composed of Navy, Marine Corps, and Coast Guard reservists, retirees and volunteers. 1916 saw the establishment of the United States Naval Reserve Force. Unfortunately, only those persons with prior Naval service could affiliate. This left the Naval Militias as the only avenue for landlubbers to become sailors. The National Defense Act of 1916 resulted in the creation of the National Naval Volunteers, which the New York Naval Militia joined en-masse.