Gneisenau was a World War II Scharnhorst class capital ship, referred to as either a light battleship or battlecruiser of the German Kriegsmarine. This 31,100-ton ship was the third to carry the name of the Prussian general August von Gneisenau, after the three-masted iron-hulled frigate SMS Gneisenau, which was launched in 1879 and wrecked in 1900; and the World War I armored cruiser SMS Gneisenau, destroyed in the battle of the Falkland Islands in 1914. 
Kreigsmarine BattleCruisers - Gneisenau Class ==========================================================================
Gneisenau was often seen in the company of her sister ship Scharnhorst, and the two ships became known as the "ugly sisters" due to their usual prowling together, and the amount of havoc they caused to British shipping.
The Scharnhorst class were the first capital ships built for the German Navy (Kriegsmarine) since World War I. They marked the beginning of German naval rearmament after the Treaty of Versailles.
They are sometimes known as the Gneisenau class since the Gneisenau was the first to be laid down and commissioned but they are also referred to by some as the Scharnhorst class as the Scharnhorst was the one that was launched first.
They were the first class of German ships to be officially classified by the Kriegsmarine as Schlachtschiff (battleship). Previous German battleships were classified as Linienschiffe (ship of the line) and Panzerschiffe (armoured ship). Their adversary, the Royal Navy, rated them as battlecruisers, although another adversary, the United States Navy, rated them as battleships; and in English language reference works either designation may be used. They traded off large-calibre guns for their 32 to 33 knot (60 km/h) speed albeit, but still achieved good armour protection, in the tradition of World War I Kaiserliche Marine battlecruisers.
Like the "pocket battleships" of the Deutschland class, Scharnhorst and Gneisenau were political compromises, powerful enough to be symbols of international power and prestige for the Nazi regime, but not so big as to overly concern international opinion or inflame the British.
She was laid down in February 1934, at Deutsche Werke Kiel. Construction was, however, delayed. She was then redesigned and re-laid in May 1935. When completed, she displaced just under the Washington Naval Treaty limit of 35,000 tons though Germany had never been covered by that Treaty.
The two ships came about as Hitler's Germany moved away from compliance with the Treaty of Versailles which had limited its military strength since the end of the First World War - specifically that no German battleship should be greater than 10,000 tons. Further building of the pocket battleships of the Deutschland class was curtailed and the guns freed up were used to arm the new ships. They were officially declared to be of some 26,000 tons displacement which while greater than the Treaty demanded was less than the 35,000 tons that the major naval powers had limited themselves to under the Washington Naval Treaty and subsequent treaties. In reality their standard displacement was some 32,000 tons, which was much more than what allowed, as with earlier Deutschlands that were officially only 10,000 tons, but over 16,000 tons in reality.
The launching ceremonies themselves paid tribute to their forebearer namesakes - the widows of the captains of the original Gneisenau and Scharnhorst, armoured cruisers that had been lost during the Battle of the Falkland Islands in the First World War, performing the christening.
In outward appearance, they were considered beautiful ships, and they looked very similar to the following Bismarck class battleships, although they only had three main gun turrets to the Bismarck's four. Unlike the Bismarck class where the Bismarck had been sunk before having a chance to operate together with her sister ship, Tirpitz, both Scharnhorst-class vessels saw combat action together for much of their careers, so they were nicknamed the "Twins" or the "Ugly Sisters". All of the ships were designed for an extended range to allow for commerce raiding.
Gneisenau carried a main armor belt of 350 mm (13.78 inch), comparable to modern battleships of the time, and vastly heavier than the World War I British battlecruisers HMS Renown and HMS Repulse and the French fast battleships Dunkerque and Strasbourg.
The ships were built with nine 28 cm (11 inch) SKC/34 guns in three triple turrets, two forward and one aft. Although the number and firepower of guns were an improvement on the preceding Deutschland class, their overall main firepower was inferior to any Royal Navy or French capital ship of the time, although only slightly in some cases. They were no match for the 380 mm (15 inch) guns of most of the battleships of her day, having firepower almost comparable to that of the British Queen Elizabeth and Revenge class battleships 15 inch (381 mm) guns due to the high muzzle velocity of the more modern guns which gave the relatively light-weight projectiles long range and good belt penetration power, but at a cost of deck penetration power.
The choice of guns was determined by both military and political factors. Some in the German navy wanted to use a considerably larger calibre of gun, either 350mm or 380mm. The decisive argument for use of the 28-cm gun was political: the British were calling for a reduction on the size limit on battleship guns, and by adopting a low calibre Hitler hoped to gain an advantage in negotiations. Furthermore, the 28-cm type was readily available, while a larger gun would have required design, testing and construction, delaying the ships by at least two years. Agreement was reached that the turrets would later be able to accommodate 38-cm guns, though the technical details of this proposal were not worked out until 1942; it is misleading to say that this conversion was planned all along.
The turrets were named, in order from the bow of the ship: "Anton", "Bruno" and "Cäsar". Similarly to most German installations, those turrets had an electric system of rotation, but all other operations were hydraulic systems. Although rotating mass of the turret was 750 tonnes (internal barbette diameter 10.2 m), traversing speed was revealed to be quite good - 7.2 deg/min. Elevation was 8 deg/min. Distance between axes of guns was 2,750 mm. Maximum elevation was +40 degrees, and the maximum depression (how far a weapon can be pointed down) was -8 degrees for turrets "Anton" and "Cäsar", and -9 degrees for the higher placed "Bruno" turret.
The 283 mm SKC/34 gun was relatively fast loading, comparing with other armament of this size. It could deliver a shot every 17 seconds. The ship magazines had a large capacity; they held 3x450 shells (150 per gun) of each of three types: armour-piercing, semi-armour-piercing, and igniting.
If a later proposal to upgrade the main armament to six 15-inch (380 mm) guns in three twin turrets, had been implemented, Gneisenau would have been a very formidable opponent, faster than any British capital ship and as well armored. When Gneisenau was designed, no 380mm guns were available for the German Kriegsmarine. It was decided to go ahead with 280mm guns, because as a commerce raider, she was not intended to fight a capital ship. Instead, superior speed would be used to avoid an engagement with a battleship. Due to priorities and constraints imposed by World War II, she retained her 11-inch guns throughout her career. Both Gneisenau and her sister were designed for an extended range to allow for commerce raiding.
It was planned to re-arm the Scharnhorst and Gneisenau with 38 cm/52 (14.96") SK C/34; replacing triple 28-cm turrets with twin 38-cm turrets. No serious work ever started for Scharnhorst, but three turrets were built during the early 1940s to rearm Gneisenau. When Gneisenau was badly damaged in 1943, these three turrets plus an additional one originally intended for the Soviet Union were reallocated for use as coastal artillery. These were to be installed at Cap de la Hague and at Paimpol in France, but this plan was never implemented. Work on putting two of these turrets at Oxsby in Denmark was well advanced but incomplete by the end of the war.
Gneisenau was considered a handsome ship, and looked as fast as she was. She and her sister ship, 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 above the water, the "freeboard", which made them "wet" when at heavy seas. This led to alterations in the sheer line and installation of the 'Atlantic Bow' in a winter 1938 refit. She conducted Battle training trials in the Atlantic in August-November 1938.
The class's military service started soon after the start of World War II, with Gneisenau and Scharnhorst hunting Allied convoys in North Sea.
On 9 September 1939, six days after war was declared, she was attacked by Royal Air Force aircraft at Brunsbüttelkoog with no damage. On 8 October, she steamed with the cruiser Köln and 9 destroyers to create a diversion against the Allied forces searching for the Deutschland.
On 23 November 1939, while attempting to break through the Iceland Gap to attack Allied ships in the North Atlantic, the two ships were sighted by British armed merchant cruiser HMS Rawalpindi. Although Rawalpindi was sunk after a short engagement, she had managed to signal the German ships' location back to base, forcing them to return to Germany.
The first major operations of the two ships against enemy warships were in the Norwegian Campaign in 1940. Thereafter they acted as a constant threat to shipping and did sink a substantial tonnage of merchant vessels. They had the effect, even when in port, of tying down Royal Navy battleships in the convoy support role. They spent a while at Brest on the French Atlantic coast where they were in position to sortie against convoys bringing supplies and materiel from the US to Britain. Here they were exposed to attacks by air, and in the Channel Dash they sped through the English Channel to more protected anchorages in Northern Europe. Once there they were no longer a threat to the Atlantic convoys but they instead posed a deadly challenge to Arctic convoys carrying supplies from Britain to the Soviets through Murmansk.
In April 1940, during the the invasion of Denmark and Norway (Operation Weserübung), Scharnhorst, Gneisenau and escorting destroyers were steering due north some 50 miles off Vestfjord, when they encountered the British battlecruiser Renown under the command of Vice-Admiral Sir William Whitworth. Renown had been rebuilt just before the war, increasing the effectiveness of her main armament. "It was now blowing a full gale, with mountainous seas and sudden curtains of snow or rain. At 0405 the Renown opened fire with her 15-inch guns at a range of about 15,000 yards. Twelve minutes later she knocked out the Gneisenau's main gunnery control system, which persuaded the Germans to run for it. In the stern chase now ensuing, Whitworth hit the Gneisenau twice again at 0434 and knocked out a forward turret. However the weather itself was on the side of the German ships as Whitworth was later to recall: The chief feature of this running action was a heavy head sea, which forced Renown to slow down in order to fight her fore turrets. The Germans on the other hand could disregard the damaging effects of heavy water coming over their forecastles and continue to fight their after turrets whilst steaming at high speed. It is noteworthy that the Germans always jinked when they saw salvoes fired, thus throwing the Renown's shots out of line. Although at times Whitworth drove Renown up to 29 knots, the two German ships had disappeared from view amid the squalls by 0660." Renown was hit twice by the Germans in this engagement.
On 5 May, Gneisenau set off a magnetic mine about 21 meters off her port quarter, and suffered shock damage, flooding, and loss of steering for 18 minutes. The damage was repaired by 21 May at Kiel. In the British withdrawal from Norway on 8 June, she and Scharnhorst surprised and sank the old British aircraft carrier HMS Glorious and her two escorts, the destroyers HMS Acasta and Ardent.
Gneisenau was torpedoed in the North Atlantic in June by HMS Clyde and forced to return to the port of Trondheim, Norway, for repairs.
After repairs, she re-joined Scharnhorst in their most successful commerce raiding campaign - from January to March, 1941 (Operation Berlin) - with Gneisenau sinking 14 ships and Scharnhorst sinking eight, mostly from unescorted convoys. They avoided the British battleships operating as convoy escorts.
The two ships returned from the open Atlantic to the port of Brest, France, and then started preparations for their next operation. Gneisenau went into the dry dock for minor repairs. In early April, 1941, an unexploded bomb, dropped by RAF Bomber Command bombers during near constant air-raids on the ships, forced Gneisenau out of drydock, and she was anchored in the inner harbor. 22 Squadron of the RAF, a Coastal Command unit based at St. Eval was sent to attack Gneisenau. As a result, Gneisenau was torpedoed on 6 April 1941, reportedly by Flying Officer Kenneth Campbell. The damage was heavy and Gneiseau was put back into drydock - only to be further damaged by four aerial bombs on the night of 9 April-10 April. She underwent repairs at Brest through December, 1941.
In 1942, Gneisenau and Scharnhorst, accompanied by the heavy cruiser Prinz Eugen, and a covering screen of destroyers and torpedo boats, executed a daring daylight run to Germany, Operation Cerberus. All three of the major ships escaped damage in the furious air and sea battles that ensued in the English Channel. Gneisenau and Prinz Eugen severely damaged the destroyer HMS Worcester. Several salvos from Gneisenau destroyed the starboard side of the bridge. and the no. 1 and 2 boiler rooms. Prinz Eugen hit the destroyer a further four times, setting it on fire. Gneisenau later struck a naval mine off Terschelling, Netherlands, and she required repairs at Kiel.
In the air attacks on 26 February-27 February 1942, on the floating dock where she was being repaired for her mine damage, she became the target of massive RAF attacks by 178 bombers, and she was struck in her bow. Contrary to the normal practice, and since repairs were anticipated to be completed within two weeks, her ammunition had not been unloaded. The resulting fires set off an explosion that destroyed her entire bow section. After emergency bow repairs, Gneisenau steamed under her own power to Gotenhafen, where she was decommissioned while reconstruction work could be engaged in.
Gneisenau was completely withdrawn from service in July 1943 to allow for repairs. Scharnhorst moved further North to partner the Tirpitz, but was sunk after encountering a heavy RN force during an attack on a convoy in the "Battle of North Cape" 26 December 1943. During Gneisenau's repairs, moves were made to rearm the ship with 38-cm (15 inch) guns. Additionally, it was planned to lengthen her bow section by 10 meters, and also replace all her 15 cm and 10.5 cm naval guns with 22 (in 11 dual closed turrets) 128 mm dual-purpose guns, but after the sinking of Scharnhorst all work was stopped and Gneisenau was sunk as a blockade ship in Gotenhafen (Gdynia) in 1945, at the end of the war.
The Gneisenau was decommissioned in 1943 and then dearmed, with her guns then used in coastal fortifications in Denmark. In 1952, Denmark emplaced two of the twin [15cm] mountings as coastal defense guns at Fort Stevns. These mountings were reduced to reserve status in 1984, but as of 1994 they were still being fired every year as part of mobilization training.
One of the 38 cm guns intended for her rearmament exists today at the museum of Hanstholm in Denmark. This gun was planned as part of the German coastal battery "Tirpitz" at Oksby, Denmark, not far from the Blåvand lighthouse on the southwest coast of Jylland. The original 38 cm guns at Hanstholm (numbers 70,71,74 and 75) were destroyed during the 1950s. Her 28 cm guns from the turret called Anton were removed and sent to the Netherlands for use there; the turrets called Bruno and Cäsar and their guns were sent to Norway for coastal defence artillery there.
Her aft main turret, called Cäsar, was converted to a coastal battery named Austråt fort in Ørland near Trondheim, Norway, and it still exists today as a museum. The second turret called Bruno was stationed as a coastal battery at Fjell fortress near Bergen. Only the concrete base still stands. In Denmark, at the former "Stevnsfort" near Rødvig, two twin 15 cm turrets from her secondary armament still exist. In the Netherlands, parts of the guns of turret Anton are on display at the former "Stichting Fort", Hoek Van Holland.
=================================================================================
NB: The above text has been collected / excerpted / edited / mangled / tangled / re-compiled / etc ... from the following online sources :
KM - BattleCruiser Gneisenau - wikipedia article #1
KM - Scharnhorst Class BattleCruiser - wikipedia article #2
