2018 $10 WWI Centennial-German U-Boats, Mint Souvenir Sheet, Bequia

This $10 mint souvenir sheet was issued in 2018 by Bequia, one of the Grenadines of St. Vincent, as part of a WWI Centennial series focused on German U-boats. The single stamp within the sheet depicts the RMS Lusitania alongside the German submarine SM U20 — the U-boat responsible for sinking her — with the Imperial German naval ensign visible in the upper corner. The sheet background features two wartime artifacts: a dramatic Allied propaganda poster from the sinking of the hospital ship HMHS Llandovery Castle, and a period silhouette recognition chart showing German aircraft including the DFW biplane. The number 1804 in the lower right corner is the sheet's serial number.

The sinking of the Lusitania on May 7, 1915, by SM U20 off the coast of Ireland was one of the defining events of World War I. The British ocean liner was struck by a single torpedo and sank in just 18 minutes, killing 1,198 of the 1,959 people on board, including 128 American citizens. The attack outraged public opinion on both sides of the Atlantic and played a significant role in shifting American sentiment against Germany, though the United States did not formally enter the war until 1917. Germany's policy of unrestricted submarine warfare — targeting any vessel in the war zone, including neutral ships — became one of the central justifications for America's eventual entry into the conflict.

The propaganda poster visible in the sheet's background references another notorious U-boat attack: the sinking of HMHS Llandovery Castle, a Canadian hospital ship torpedoed by U-86 in June 1918, with the loss of 234 lives. Hospital ships were protected under international law, making the attack a war crime. The poster's slogan — "Victory Bonds Will Help Stop This — Kultur vs. Humanity" — captures the moral outrage that Allied governments used to drive public support for the war effort.