First World War (1914-1918)
The U-Boat Menace

The emergence of the submarine was a major development in naval warfare. German submarine - or U-Boat - attacks against Allied shipping in the Atlantic and in European waters posed a major threat to the Allied war effort.

HMHS Llandovery Castle

A group of passengers, mostly Canadian soldiers, pose for a photograph on board the Canadian hospital ship HMHS Llandovery Castle on 26 May 1918.

Just over a month later, the German submarine U-86 torpedoed and sank the well- marked hospital ship, which had been carrying civilians, nurses, and wounded soldiers, off the Irish coast. The sub then rammed the ship's lifeboats and machine-gunned survivors in the water. Fourteen Canadian nursing sisters were among the 234 dead from the Llandovery Castle; only 24 people survived.

George Metcalf Archival Collection
CWM 20070096-010