HMS Legion was a Laforey-class destroyer built for the Royal Navy during the 1910s.
The Laforey class were improved and faster versions of the preceding Acasta class. They displaced 965–1,010 long tons (980–1,026 t). The ships had an overall length of 268 feet 10 inches (81.9 m), a beam of 27 feet 8 inches (8.4 m) and a draught of 10 feet 6 inches (3.2 m). Legion was powered by two Parsons direct-drive steam turbines, each driving one propeller shaft, using steam provided by four Yarrow boilers. The turbines developed a total of 24,500 shaft horsepower (18,300 kW) and gave a maximum speed of 29 knots (54 km/h; 33 mph). The ships carried a maximum of 280 long tons (280 t) of fuel oil that gave them a range of 1,750 nautical miles (3,240 km; 2,010 mi) at 15 knots (28 km/h; 17 mph). The ships' complement was 74 officers and ratings.
The ships were armed with three single QF 4-inch (102 mm) Mark IV guns and two QF 1.5-pounder (37 mm) anti-aircraft guns. These latter guns were later replaced by a pair of QF 2-pounder (40 mm) "pom-pom" anti-aircraft guns. The ships were also fitted with two above-water twin mounts for 21-inch (533 mm) torpedoes. They were equipped with rails to carry four Vickers Elia Mk IV mines, although these rails were never used.
Two destroyers of the British Royal Navy have been named HMS Legion, after the Roman legion.
HMS Legion was an L-class destroyer of the Royal Navy. She entered service during the Second World War, and had a short but eventful career, serving in Home waters and the Mediterranean. She was sunk in an air attack on Malta in 1942. The ship had been adopted by the British civil community of the Municipal Borough of Cheltenham, Gloucestershire in November 1941.
Legion was ordered on 31 March 1938 from the yards of Hawthorn Leslie and Company, Newcastle upon Tyne under the 1937 Naval Estimates. She was laid down on 1 November 1938 and launched just over a year later on 26 November 1939. During 1940 her main armament along with three others of the L class was changed. Twin 4 inch HA mountings were fitted and these four ships were re-classified as anti-aircraft destroyers. She was commissioned on 19 December 1940 at a total cost of £445,684, which excluded items such as weapons and communications equipment supplied by the Admiralty. During trials, a number of defects were revealed, resulting in the ship being under repair at Greenock in Scotland until January 1941.