World War I German Navy Officer. A Kapitanleutnant in the Imperial German Navy's Submarine service, he was in command of the German submarine that torpedoed and sank the British ocean liner "RMS Lusitania." Of a new breed of German naval officers prior to World War I, Schweiger went into the submarine service where he quickly proved to be a technically competent officer, and rose quickly in rank. With the outbreak of World War I in August 1914, the German submarine fleet was ordered to sea, to set up a blockade around Great Britain. At age 30, Schweiger was in command of the U-20, one of the German Navy's newest submarines, with a crew of 32 men. Initially, German submarines were restricted only to clear military targets: warships and merchant ships carrying war supplies. Despite this restriction, on February 1, 1915, U-20 fired at a hospital ship in the English Channel; although Schweiger missed the ship, the British soundly condemned the attack. In early 1915, the British started arming merchant ships with hidden cannons. These ships, designated as Q-boats, would then open fire on the submarine as soon as it surfaced. One hit would sink the submarine. In response to this threat, the Germans declared unrestricted warfare in February 1915, meaning that all allied ships entering the declared war zone around Great Britain would be subject to being torpedoed without warning. On the afternoon of May 7, 1915, off the coast of Ireland, U-20 fired a single torpedo into the "RMS Lusitania" without warning, striking just forward of its bridge on the starboard side. Several minutes later, a second explosion doomed the ship, and it rolled over, sinking just 18 minutes after the attack. Of the 1,969 persons aboard the ship, only 774 survived. 128 Americans also died in the attack, and the high loss of life caused great anger in the United States. Despite the criticism, Schweiger was awarded the Iron Cross for sinking the Lusitania. The following year, Schweiger sank a number of merchant ships, soon becoming one of Germany's newest U-boat Aces. In November 1916, the U-20 grounded itself off of Denmark's Jutland Peninsula, and had to send out a distress call. The responding German ships could not pull the U-20 off the sandbar, so the crew was removed and the submarine destroyed to prevent enemy capture. Schweiger was soon given command of another submarine, the U-88, and was soon back sinking British ships. On September 17, 1917, the U-88 detonated a mine while attempting to penetrate a minefield, and was lost with all hands. The bodies of the crew and the ship were never recovered. During his twelve operational patrols, Schweiger had sunk over 190,000 tons of Enemy shipping, becoming the 7th highest scoring German U-Boat commander of World War I.