The 12th Coast Artillery Regiment was a Coast Artillery regiment in the United States Army, constituted in the Regular Army on 27 February 1924. It served in the Harbor Defenses of the Chesapeake with headquarters at Fort Monroe, Virginia from 1924 to 1932. At that point, the regiment effectively became the 2nd Coast Artillery; on paper the 2nd Coast Artillery was transferred from the Harbor Defenses of Cristobal in the Panama Canal Zone and the 12th was transferred to that harbor defense. However, the 12th was never activated again, and on 19 June 1944 was disbanded.

Fort Monroe is a former military installation in Hampton, Virginia, at Old Point Comfort, the southern tip of the Virginia Peninsula, United States. It is currently managed by partnership between the Fort Monroe Authority for the Commonwealth of Virginia, the National Park Service, and the city of Hampton as the Fort Monroe National Monument. Along with Fort Wool, Fort Monroe originally guarded the navigation channel between the Chesapeake Bay and Hampton Roads—the natural roadstead at the confluence of the Elizabeth, the Nansemond and the James rivers.