The Maine State Guard was the state defense force of the state of Maine during World War I, World War II, and the Vietnam War. As a state defense force, the State Guard served as a stateside replacement for the Maine National Guard when the National Guard was federalized. Like the National Guard, the State Guard was a reserve military force composed of members who held full-time civilian jobs and periodically met for drills, unless called into active service by the governor. However, unlike the National Guard, as a state defense force, the Maine State Guard was solely a state military force, which was immune from federalization and could not be deployed outside the state of Maine.