The United Empire of Earth (UEE) Navy is the largest branch of the UEE's armed forces. It is responsible for the operation of capital spacecraft, support ships, and fighters and the maintenance thereof. The UEE Navy is headed by the Legatus Navium, who represents the branch in the military High Command. It is headquartered at MacArthur (Kilian V) in the Kilian system. The Navy is responsible for operations outside of UEE territory in times of war and for acting as an additional security presence to support law enforcement within the UEE's borders.