Marine Detachment

Marine Detachment aboard the USS Augusta (CA-31) in the 1930s

Marine Detachment or MarDet was a unit of 35 to 55 United States Marines aboard battleships or aircraft carriers. They were a regular component of a ship's company since the formation of the United States Marine Corps up until the 1990s. Missions of the Marine Detachment evolved over time, and included protecting the ship's captain, security and defense of the ship, operating the brig, limited action ashore, securing nuclear weapons and ceremonial details.