The Gneisenau and her sister Scharnhorst were large heavy gun warships of World War II vintage of the German navy, or Kriegsmarine. Due to the cost and prestige of such ships, they are often referred to as "capital ships".

Like the "pocket battleships" of the Deutschland class, Scharnhorst and Gneisenau were political compromises, symbols of international power for the Hitler regime, but designed not to overly inflame the British. The Royal Navy refers to them as "battlecruisers" [1] (http://www.royal-navy.mod.uk/static/pages/3542.html), as do most references which use Royal Navy sources, because they traded extra guns for their 32 to 33 knot (60 km/h) speed and extended range to allow for commerce raiding. As their designed main armament wasn't ready in time, they initially carried 9-11 in (280 mm) guns in three triple turrets, two forward and one aft, inferior to any Royal Navy capital ship of the time. If they had carried their designed main armament of 6-15 in (380 mm) guns in three twin turrets, they would have been formidable opponents, faster than any British capital ship and nearly as well armored. But due to Hitler's shifting attitudes towards the surface navy and the priorities of war, they retained their 11 in (280 mm) guns in triple turrets, like the Deutschland's, throughout their careers.

Gneisenau was built by Deutsche Werke Kiel, laid down in February of 1934. Construction was delayed and then scrapped as the design changed, and she was re-laid in May of 1935. She was launched in late 1936 and commissioned in 1938. She was 771 ft (235 m) in length, 98 ft (30 m) in beam and displaced just under the naval treaty limit of 35000 tons. She carried a main armor belt of nearly 14 in (350 mm), comparable to modern battleships of the time, and vastly heavier than the British battlecruisers HMS Renown and HMS Repulse, ships which would have been her equal in main battery as designed. It is often said that she was a handsome ship, and looked as fast as she was. She and her sister Scharnhorst are generally spoken of as the most successful German design of the period. The main criticism of the design was their relatively low deck height, or "freeboard", which made them "wet" in North Atlantic conditions.

In late 1939 she operated with Scharnhorst in the North Atlantic and sank a minor British warship, but suffered severe sea damage in a storm. In 1940 she covered the Norway invasion and fought with HMS Renown to no conclusion. In the British withdrawal she and Scharnhorst surprised and sank the old British carrier HMS Glorious, herself a converted battlecruiser, and her two escorts. She was torpedoed in the North Atlantic in June, and after being repaired joined Scharnhorst in their most successful merchant campaign in March, 1941, Gneisenau sinking 14 ships, Scharnhorst sinking 8, and managing to keep out of the way of British battleships covering the convoys. She was torpedoed again in April 1941 and repaired at Brest in France.

In 1942 British air attacks made Brest unsafe, and accompanied by Scharnhorst, the heavy cruiser Prinz Eugen and a covering screen of destroyers and torpedo boats, she attempted a daring daylight run to Norway, known ever after as the "Channel Dash", as part of the reinforcement of the country following the Commando raid on Vaagso. Although she escaped damage in the furious air battles that resulted, she struck a mine that laid her up at Kiel, where she was badly damaged in a bombing raid that was to end her career. Some work was done in 1942-1944 to reconstruct her with the twin 15 in (380 mm) guns, but it never came to fruition. Her final sad duty was to be used as a blockship, sunk in Gotenhafen harbor. She was broken up and scrapped after the war. Her aft main turret, "Caesar", converted to a coastal battery named Austråt Fort, is still existing today near Trondheim, Norway.