<human>:  When did the Lusitania sink?
<bot>: The RMS Lusitania was sunk by a German U-boat on May 7, 1915. The ship was carrying over 1,000 passengers and crew, mostly Americans, from New York to Liverpool, England. The ship was struck by a torpedo from the German submarine, and sank in just over two hours. The ship was carrying over a ton of explosives and was packed with ammunition.