HMS Hood (pennant number 51) was the last battlecruiser built for the Royal Navy. One of four Admiral-class battlecruisers ordered in mid-1916, her design—although drastically revised after the Battle of Jutland and improved while she was under construction—still had serious limitations. For this reason she was the only ship of her class to be completed. She was named after the 18th-century Admiral Samuel Hood. Construction of Hood began at the John Brown & Company shipyards in Clydebank, Scotland, on 1 September 1916. Following the loss of three British battlecruisers at the Battle of Jutland, 5,000 tons of extra armour and bracing were added to Hood's design.
Hood was involved in a number of flag-waving exercises between her commissioning in 1920 and the outbreak of war in 1939; these included training exercises in the Mediterranean Sea and a circumnavigation of the globe with the Special Service Squadron in 1923 and 1924. She was attached to the Mediterranean Fleet following the outbreak of the Second Italo-Abyssinian War. When the Spanish Civil War broke out, Hood was officially assigned to the Mediterranean Fleet until she had to return to England in 1939 for an overhaul. At this point in her service, Hood's usefulness had deteriorated because of advances in naval gunnery. She was scheduled to undergo a major rebuild in 1941 to correct these issues, but the outbreak of World War II forced the ship into service without the upgrades.