The class answered an early battle-fleet problem: an enemy cruiser might defeat torpedo-boat destroyers before they could protect the battle line. Its 9.2-inch and 6-inch batteries were therefore aimed at hostile cruisers rather than battleships. The same range and armament made the ships credible against surface raiders and useful on distant convoy duties. The class combined battle-fleet reconnaissance with traditional trade protection in one hull. That requirement reflected a 1903 threat picture in which surface raiders mattered more immediately than still-immature submarines. The far greater submarine capabilities seen in 1916 and 1942 show how quickly the design environment changed.
Chapter · 3:30-5:52
Armoured cruisers built for the battle fleet
The Duke of Edinburgh class was designed to scout for the battle fleet and defeat opposing cruisers, while retaining the reach for traditional trade-protection work.