Scharnhorst was a German Kriegsmarine capital ship during the Second World War. It was the lead of her class, referred to as either a battleship or a battlecruiser. The 31,500 t (31,000 long tons) ship was named after the Prussian General and army reformer Gerhard von Scharnhorst and to commemorate the First World War armored cruiser SMS Scharnhorst that was sunk in the Battle at the Falkland Islands in December 1914. Scharnhorst often sailed into battle accompanied by her sister ship, Gneisenau. Scharnhorst sailed on many naval operations in 1939—1941 with significant success. In December 1943, she took part in the German Operation Ostfront to engage Arctic Convoys sent by the Western Allies to the Soviet Union. Royal Navy—led Allied forces engaged Scharnhorst. In the subsequent Battle of North Cape, the ship was sunk.
Scharnhorst was built at Wilhelmshaven, Germany, launched on 3 October 1936, and commissioned on 7 January 1939. The first commander was Otto Ciliax (until 23 September 1939). After initial service, she was modified in mid-1939, with a new mainmast located further aft and her straight bow replaced by an "Atlantic bow" to improve her seaworthiness. However, her relatively low freeboard ensured that she was always "wet" in heavy seas. The gunnery report after the engagement with the British battlecruiser HMS Renown reports serious flooding in the "A" turret that severely reduced its effectiveness. Her armor was equal to that of a battleship and if it had not been for her relatively small-caliber guns she would have been classified as a battleship by the British. The German navy always classified Scharnhorst and Gneisenau as Schlachtschiffe (battleships). These two ships — considered handsome and fast (with a top speed of 31.5 kn (58.3 km/h; 36.2 mph)) — were invariably mentioned at the same time, often fondly being referred to as "the ugly sisters".
Scharnhorst's nine 28 cm (11 in) (in fact, 28.3 cm (11.1 in)), main guns, though possessing long range and quite good armor-penetration power because of their high muzzle velocity, were no match for the larger caliber guns of most of the battleships of her day, particularly with the flooding and technical problems that were experienced. The choice of armament was a result of their hasty commissioning.
If a later proposal to upgrade the main armament to six 38 cm (15 in) guns in three twin turrets had been implemented, Scharnhorst might have been a very formidable opponent, faster than any British capital ship and nearly as well armored. But due to priorities and constraints imposed by World War II and later the war situation, she retained her 28 cm (11 in) guns throughout her career. Both Scharnhorst and her sister were designed for an extended range to allow for commerce raiding.