The St Nazaire Raid or Operation Chariot was a British amphibious attack on the heavily defended Normandie dry dock at St Nazaire in German-occupied France during the Second World War. The operation was undertaken by the Royal Navy (RN) and British Commandos under the auspices of Combined Operations Headquarters on 28 March 1942. St Nazaire was targeted because the loss of its dry dock would force any large German warship in need of repairs, such as Tirpitz, sister ship of Bismarck, to return to home waters by running the gauntlet of the Home Fleet of the Royal Navy and other British forces, via the English Channel or the North Sea.

The Commandos, also known as the British Commandos, were formed during the Second World War in June 1940, following a request from Winston Churchill, for special forces that could carry out raids against German-occupied Europe. Initially drawn from within the British Army from soldiers who volunteered for the Special Service Brigade, the Commandos' ranks would eventually be filled by members of all branches of the British Armed Forces and a number of foreign volunteers from German-occupied countries. By the end of the war 25,000 men had passed through the Commando course at Achnacarry. This total includes not only the British volunteers, but volunteers from Greece, France, Belgium, Netherlands, Canada, Norway and Poland. The United States Army Rangers and US Marine Corps Raiders, Portuguese Fuzileiros Portuguese Marine Corps were modelled on the Commandos.