Naval operations, German World War, 1939-1945 63 Naval operations 46 Submarine 44 History 25 Campaigns 18 World War, 1914-1918 18 more ... Naval operations, British 9 Submarines (Ships) 8 Naval operations, American 5 Sailors 5 History, Naval 4 Military relations 3 Naval operations, Canadian 3 Shipwrecks 3 Anti-submarine warfare 2 Coast defenses 2 Cryptography 2 Naval operations, Japanese 2 Naval operations, Soviet 2 Officers 2 Sea-power 2 Submarine warfare 2 Art 1 Boundaries 1 Childhood and youth 1 Children 1 Children and war 1 Cities and towns 1 Cruisers (Warships) 1 less ...