RMS Lusitania Sinking of the RMS Lusitania. RMS Lusitania RMS "Lusitania" was a British ocean liner and briefly the world's largest passenger ship. The ship was sunk on 7 May 1915 by a German U-boat off the southern coast of Ireland. The sinking presaged the United States declaration of war on Germany in 1917. The ship was a holder of the Blue Riband appellation for the fastest Atlantic crossing and was briefly the world's largest passenger ship until the completion of her sister ship . The Cunard Line launched "Lusitania" in 1906, at a time of fierce competition for the North Atlantic
RMS Mauretania (1906) of Mauretania on the northwest African coast, not the modern Mauritania to the south. Similar nomenclature was also employed by "Mauretania"s running mate , which was named after the Roman province directly north of Mauretania, across the Strait of Gibraltar in Portugal. "Mauretania" remained in service until 1934 when Cunard White Star retired her; scrapping commenced in 1935. In 1897 the German liner became the largest and fastest ship in the world. With a speed of , she captured the Blue Riband from Cunard Line's and . Germany came to dominate the Atlantic, and by 1906 they had five four-funnel