Gneisenau () was a German capital ship, alternatively described as a battleship and battlecruiser, of Nazi Germany's Kriegsmarine. She was the second vessel of her class, which included her sister ship, . The ship was built at the Deutsche Werke dockyard in Kiel; she was laid down on 6 May 1935 and launched on 8 December 1936. Completed in May 1938, the ship was armed with a main battery of nine 28 cm (11 in) C/34 guns in three triple turrets. Plans were approved, once construction had started, to replace these weapons with six 38 cm (15 in) SK C/34 guns in twin turrets, but as this would involve a lot of redesign, construction continued with the lower calibre guns. The intent was to make the upgrade in the winter of 1940–41, but the outbreak of World War II stopped this.
Gneisenau and Scharnhorst operated together for much of the early portion of World War II, including sorties into the Atlantic to raid British merchant shipping. During their first operation, the two ships sank the British auxiliary cruiser in a short battle. Gneisenau and Scharnhorst participated in Operation Weserübung, the German invasion of Norway. During operations off Norway, the two ships engaged the battlecruiser and sank the aircraft carrier . Gneisenau was damaged in the action with Renown and later torpedoed by a British submarine, , off Norway. After a successful raid in the Atlantic in 1941, Gneisenau and her sister put in at Brest, France. The two battleships were the subject of repeated bombing raids by the RAF; Gneisenau was hit several times during the raids, though she was ultimately repaired.
In early 1942, the two ships made a daylight dash up the English Channel from occupied France to Germany. After reaching Kiel in early February, the ship went into drydock. On the night of 26 February, the British launched an air attack on the ship; one bomb penetrated her armored deck and exploded in the forward ammunition magazine, causing serious damage and many casualties. The repairs necessitated by the damage were so time-consuming that it was determined to rebuild the ship to replace the nine 28 cm guns with six 38 cm guns in double turrets. The 28 cm guns were removed and used as shore batteries. In 1943, Hitler ordered the cessation of conversion work, and on 27 March 1945, she was sunk as a blockship in Gotenhafen (Gdynia) in German-occupied Poland. She was eventually broken up for scrap in 1951.
Design
Gneisenau displaced at standard displacement and at full load. She was long overall and had a beam of and a maximum draft of . She was powered by three Germania geared steam turbines, which developed a total of and yielded a maximum speed of on speed trials. Her standard crew numbered 56 officers and 1,613 enlisted men, though during the war this was augmented up to 60 officers and 1,780 men. While serving as a squadron flagship, Gneisenau carried an additional ten officers and 61 enlisted men.
She was armed with a main battery of nine 28 cm (11.1 in) L/54.5 guns arranged in three triple gun turrets: two turrets were placed forward in a superfiring arrangement—Anton and Bruno—and one aft—Caesar. Her secondary armament consisted of twelve 15 cm (5.9 in) L/55 guns, eight of which were placed in two-gun turrets and the remaining four were carried in individual turrets. Her anti-aircraft armament consisted of fourteen L/65 and sixteen SK C/30 L/83, and initially ten C/30 anti-aircraft guns. The number of 2 cm guns was eventually increased to thirty-eight. Six above-water torpedo tubes, taken from the light cruisers and , were installed in 1942.
Gneisenau had an armor belt that was thick in the central portion, where it protected the ship's ammunition magazines and propulsion machinery spaces. The ship had an armor deck that was thick on the flat portion, increasing to on downward-sloping sides that connected to the bottom of the belt. Her main battery turrets had of armor on their faces and on their sides. The conning tower was protected with 350 mm on the sides.
