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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
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.

CWM 19910113-001

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The Return of U-9
U-Boat Deck Gun
Periscope Lens, U-117
U-Boat Signalling Lamp
Cut-Away German U-Boat Mine
German Naval Mine, U-153
SS Audax Sinking
Life Ring, SS Brussels
Life Ring, UC-77
"We risk our lives to bring you food. It's up to you not to waste it."
Porthole, RMS Lusitania
Qu'importe l'existence des Neutres! L'Allemagne est au dessus de tout! (Neutrality is irrelevant! Germany sees herself above all else!)
HMHS Llandovery Castle
Depth Charge, "Type G"
Model, U-27
First World War Atlantic Convoy
German Submarine U-118