Merchant raider

The captain of a German merchant raider, Felix von Luckner, used the sailing ship SMS Seeadler for his voyage (1916–1917).

Several captains demonstrated great creativity in disguising their vessels to masquerade as allied or as neutral merchants.

The Kormoran fought the Australian light cruiser Sydney in a mutually destructive battle in November 1941.

Generally adapted from passenger liners, they were larger than the German merchant raiders, were used as convoy escorts and did not disguise themselves.

During World War I, the British Royal Navy deployed Q-ships to combat German U-boats.