In the early 20th century Britain's largest colonies established their own small naval presence, and their ships fought alongside the Royal Navy during World War I. These fleets were expanded slightly during the inter-war years, and in 1939 the Royal Australian Navy, the Royal Canadian Navy and the Royal New Zealand Navy willingly joined the fight on behalf of the British Commonwealth. For the most part these small navies consisted of a few cruisers and destroyers, designed to protect territorial waters and to protect local sea lanes. However, these warships and their crews soon found...