Roman navy
The Roman navy (Latin: "classis," "fleet") not only aided in the supply and transport of the legions but also helped in the protection of the frontiers along the rivers Rhine and Danube. Another of its duties was the protection of the crucial maritime trade routes against the threat of pirates. It patrolled the whole of the Mediterranean, parts of the North Atlantic coasts, and the Black Sea. Nevertheless, the army was considered the senior and more prestigious branch.