The Germans had launched their first unrestricted submarine campaign in 1915. U-boat commander Walther Schwieger was the captain in charge of the U20. In accordance with German decrees dated April 30, 1915 addressed to Lieutenant Commander Schwinger of Submarine 20, which gave him clear orders to attack all transport ships, merchant ships and warships as they saw fit, under no no matter which flag. “On May 7, 1915, Schwieger was responsible for the torpedoing of the liner RMS Lusitania by U-20, resulting in the deaths of 1,198 people.” (“Sinking of the RMS