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.

Porthole, RMS Lusitania

This porthole was recovered in 1982 from the ocean liner RMS Lusitania, sunk in 1915 with heavy loss of life.

In early 1915, Germany had warned Allied governments that U-Boats would sink without warning any ships carrying war supplies to Britain. On 7 May, the German submarine U-20 torpedoed the Lusitania off the coast of Ireland. The ship, carrying both civilian passengers and war supplies, sank very quickly, killing 1,198, including dozens of Canadian women and children. The sinking helped galvanize public opinion against Germany.

Porthole
CWM 19910113-001