The Eastern Sea Frontier (EASTSEAFRON) was a United States Navy operational command during World War II, that was responsible for the coastal waters from Canada to Jacksonville, Florida, extending out for a nominal distance of two hundred miles. The Commander was designated Commander, Eastern Sea Frontier (COMEASTSEAFRON). COMEASTSEAFRON had vessels for convoy use or other uses determined by the commander. In addition to providing escorts for convoys within its frontier, the frontier was responsible for sea-air rescue, harbor defense, shipping lane patrol, minesweeping, and air operations.