“Travellers intending to embark on the Atlantic voyage are reminded that a state of war exists between Germany . . . and Great Britain . . . and that travellers sailing in the war zone on ships of Great Britain or her allies do so at their own risk.”

So read a notice from the German government that ran in forty U.S. newspapers on May 1, 1915, ten months after the outbreak of World War I and three months after Germany declared a submarine blockade of the British Isles. On that day, the British luxury liner, the RMS Lusitania, set sail from New York for Liverpool; six days later, twelve miles off the southern coast of Ireland, she was torpedoed by a German submarine and sank. Of the 1,959 people on board, 1,195 died, including more than 120 Americans.

In the context of a wartime crossing, the cargo of the Lusitania on her last voyage included war materiel for the Allied war effort, including 52 tons of shrapnel shells, more than 3,000 percussion fuses, and 4,200 cases of Remington rifle cartridges. Kapitänleutnant Walter Schwieger was the thirty-year-old commander of the submarine U-20 that sank the Lusitania. His war diary describes the attack and the rapid sinking of the great liner as he viewed it through his periscope.