11. The British Admiralty knew the whereabouts of German submarines
In 1915, the British Admiralty had the ability to track German ships via radio transmissions, and they were tracking a German submarine as Lusitania departed New York. The ability of the British to track German submarines, and the information the ability developed, were both highly classified, only the most senior officers were aware of the fact. Among them was the First Lord of the Admiralty, Winston Churchill. In March 1915, British listeners learned that the Germans had cracked the code they were using to transmit submarine activity to ships at sea. Use of the code continued until after the loss of Lusitania. On May 3, the Admiralty sent a message in the clear (uncoded), warning of increased German submarine activity to all ships at sea.
The German submarine U-20 sank three ships on May 5-6 in the Irish Sea, and attempted attacks on two others without success. On May 7, shortly before noon, the Admiralty issued a warning which read, “U-boats active in southern part of Irish Channel. Last heard of twenty miles south of Coningbeg Light Vessel”. In response Lusitania turned towards the Irish coast, to pass between the submarine position reported and the light, but the submarine was much closer to the coast. Just after 1 PM, the U-20 sighted the liner and began closing it, submerged. The submarine commander, Walther Schwieger, maneuvered for about an hour before attaining a perfect firing position, from which he launched a single torpedo at Lusitania.