SMS Cormoran or SMS Cormoran II was a German armed merchant raider that was originally a Russian merchant vessel named Ryazan. The ship was active in the Pacific Ocean during World War I. Built in 1909, she was captured by the German light cruiser SMS Emden on 4 August 1914 and converted into a raider at the German colony Kiautschou. She was forced to seek port at Apra Harbor on the U.S. territory of Guam on 10 August 1914. The United States, then declared neutral in the war, refused to sufficient provisions to allow Cormoran to make a German port. After the U.S. declaration of war on April 6, 1917, the Naval Governor of Guam informed Cormoran that she would be seized as a hostile combatant, prompting her crew to scuttle her.