In 1915, Canadian Vickers in Montreal received a contract to manufacture small "H class" submarines like these for Britain's Royal Navy.

The British had ordered 20 submarines from the United States in early 1915, but America was still neutral, which interfered with the orders. The American firms contracted out 10 of the "H class" submarines to Canadian Vickers, which delivered them quickly, since many of the components had already been manufactured south of the border. Six of the submarines left Halifax for Britain on 22 July 1915 and the other four sailed a few weeks later.

George Metcalf Archival Collection
CWM 19830056-019