Plan Z was the name given to the planned re-equipment and expansion of the Kriegsmarine (German navy) ordered by Adolf Hitler in early 1939. The fleet was meant to challenge the naval power of the United Kingdom, and was to be completed by 1948. Development of the plan began in 1938, but it reflected the evolution of the strategic thinking of the Oberkommando der Marine (Naval High Command) over the two decades following World War I. The plan called for a fleet centered on ten battleships and four aircraft carriers which were intended to battle the Royal Navy. This force would be supplemented with numerous long-range cruisers that would attack British shipping. A relatively small force of U-boats was also stipulated.
When World War II broke out in September 1939, almost no work had been done on the new ships ordered under Plan Z. The need to shift manufacturing capacity to more pressing requirements forced the Kriegsmarine to abandon the construction program, and only a handful of major ships—all of which had been ordered before Plan Z—were completed during the war. Nevertheless, the plan still had a significant effect on the course of World War II, in that only a few dozen U-boats had been completed by the outbreak of war. Admiral Karl Dönitz's U-boat fleet only reached the 300 U-boats he deemed necessary to win a commerce war against Britain in 1943, by which time his forces had been decisively defeated.
Following the end of World War I, the German armed forces became subject to the restrictions of the Treaty of Versailles. For the new Reichsmarine , this meant it was limited to six pre-dreadnought battleships, six old light cruisers, 12 destroyers and 12 torpedo boats. A further two pre-dreadnoughts, two cruisers, and four destroyers and torpedo boats apiece could be kept in reserve.The first major ship to be built after the war was the light cruiser Emden in the early 1920s. This was followed by a further three light cruisers of the Königsbergclass: Königsberg, Karlsruhe and Köln, and a further two ships that were modified versions of the Königsberg class, Leipzig and Nürnberg. At the same time, the Germans created a dummy corporation, NV Ingenieurskantoor voor Scheepsbouw (IvS), in the Netherlands to secretly continue development of submarines. This was in violation of Article 191 of the Treaty of Versailles, which prohibited Germany from possessing or building submarines for any purpose. IvS built several submarines for foreign navies, including the Turkish Gür, which was the basis for the Type I U-boat, and the Finnish Vesikko, which was the prototype for the Type II U-boat.
The Treaty also stipulated that Germany could replace its pre-dreadnought battleships after they reached twenty years of age, but new vessels could displace no more than 10,000 long ton s (10,000 t ). In response to these limitations, the Germans attempted to build a powerful heavy cruiser—classified as a panzerschiff (armored ship)—that outclassed the new heavy cruisers built by Britain and France. While British and French heavy cruiser designs were bound by the Washington Naval Treaty (and subsequent London Naval Treaty) to a caliber of 20.3 cm (8.0 in) on a displacement of 10,000 tons, the Germans chose to arm Deutschland with six 28 cm (11 in) guns. The Germans hoped that by building a ship significantly more powerful than the Allies, they could force the Allies to admit Germany to the Washington treaty system in exchange for cancelling Deutschland, thereby abrogating the naval limitations imposed by Versailles. The French vehemently opposed any concessions to Germany, and therefore, Deutschland and two further units— Admiral Scheer and Admiral Graf Spee —were built.
In 1932, the Reichsmarine secured the passage of the Schiffbauersatzplan ("Replacement ship construction program") through the Reichstag . The program called for two separate production phases, the first from 1930 to 1936, and the second from 1936 to 1943. The latter phase was secretly intended to break the Versailles restrictions. 32,000-long-ton (33,000 t) ships armed with nine 28 cm guns and much greater armor protection than their predecessors. In 1935, Hitler signed the Anglo-German Naval Agreement, which permitted Germany to build up to 35 percent of the strength of the Royal Navy in all warship categories. The initial designs for two follow-on ships—the Bismarckclass —initially called for a displacement of 35,000 long tons (36,000 t) with 13 in (330 mm) guns, but to counter the two new, French Richelieu-classbattleships, the new ships were significantly enlarged, to a displacement of over 41,000 long tons (42,000 t) and 15 in (380 mm) guns.The following year, Adolf Hitler became the Chancellor of Germany. He unilaterally withdrew from the restrictions of the Treaty of Versailles and began the systematic re-building of the armed forces. The prestige brought by the Panzerschiffe led to two improved vessels, the D class, to be ordered. These ships were cancelled and reordered as the battleships Scharnhorst and Gneisenau, which were
The postwar German navy was conflicted over what direction future construction should take. In September 1920, Konteradmiral (Rear Admiral) William Michaelis issued a memorandum laying out the goals of the new Reichsmarine; these goals emphasized coastal defense rather than significant expansion. The German Army viewed Poland as the primary future enemy, and the Navy assumed that in a conflict with Poland, France would support Poland. Thus, the French Navy would be the most likely opponent for the Reichsmarine; Britain was expected to remain neutral in such a conflict. The construction of warships through the mid-1930s was primarily directed against the perceived French threat.Any hypothetical U-boats would generally support the main fleet rather than embark on a commerce-raiding campaign, and any raiding would be done strictly according to cruiser rules. This view remained the established orthodoxy until the mid-1930s, when then- Kapitän zur See (Captain at Sea) Karl Dönitz came to command the U-boat arm. Dönitz advocated a return to unrestricted submarine warfare and the adoption of wolfpack tactics to overwhelm convoy defenses.
In the 1920s, the question arose over what to do with the cruisers that would presumably be abroad on training cruises when a war would break out. The high command decided that they should operate as independent commerce raiders. When Vizeadmiral (Vice Admiral) Erich Raeder became the head of the Reichsmarine in 1928, he fully endorsed the concept of long-range surface raiders. This was in large part due to his service in World War I as the chief of staff to Vizeadmiral Franz von Hipper, where he saw the fleet rendered impotent by the crushing British naval superiority.By 1938, Hitler's aggressive foreign policy made conflict with Britain increasingly likely. He ordered that completion of Bismarck and Tirpitz be expedited, along with six new H-class battleships yet to be laid down. These eight battleships would form the core of a new battle fleet capable of engaging the British Royal Navy. Hitler nevertheless assured Raeder that war would not come until 1948.
Raeder meanwhile believed that Britain could be more easily defeated through the surface raider strategy he favored. The initial version of his plan was based on the assumption that the fleet should be centered on panzerschiffe, long-range cruisers, and U-boats to attack British commerce.These forces would tie down British naval power and allow a smaller number of battleships to operate in the North Sea. This first draft was called Plan X; a pared-down revision was renamed Plan Y, and the final version presented to Hitler was Plan Z. Hitler rejected Raeder's proposed construction plan, which led to a more balanced fleet that incorporated the battleships Hitler sought and was accepted on 1 March 1939. Raeder planned to use the battleships and aircraft carriers in task forces to support the panzerschiffe and light cruisers attacking British merchant traffic.
The plan approved by Hitler called for a surface fleet composed of the following vessels, which included all new ships built in the 1920s and 1930s:
These figures included the four Scharnhorst- and Bismarck-class battleships already built or building, the three Deutschland-class panzerschiffe and the six light cruisers already in service.To complete the core of the Plan Z fleet, six H-class battleships, three O-class battlecruisers, twelve P-class panzerschiffe, and two Graf Zeppelin-classaircraft carriers with two more of a new design, were to be built. The five ships of the Admiral Hipperclass fulfilled the mandate for heavy cruisers, while the M class of light cruisers would fulfill the requirement for light cruisers. The Spähkreuzer 1938 design would form the basis for the fleet scouts ordered in the program. On 27 July 1939, Raeder revised the plan to cancel all twelve of the P-class panzerschiffe.
In the short time from the introduction of Plan Z to the beginning of war with the United Kingdom on 3 September only two of the plan's large ships, a pair of H class battleships, were laid down; material for the other four ships had started to be assembled in preparation to begin construction but no work had been done.At the time components of the three battlecruisers were in production, but their keels had not yet been laid down. Two of the M-class cruisers had been laid down, but they were also cancelled in late September. Work on Graf Zeppelin was cancelled definitively in 1943 when Hitler finally abandoned the surface fleet after the Battle of the Barents Sea debacle.
Since the plan was cancelled less than a year after it was approved, the positive effects on German naval construction were minimal. All of the ships authorized by the plan were cancelled after the outbreak of war, with only a few major surface vessels that predated the plan completed during the conflict. These included Bismarck and Tirpitz, along with the heavy cruisers Blücher and Prinz Eugen. Without the six H-class battleships or the four aircraft carriers, the Kriegsmarine was once again unable to meet the Royal Navy on equal terms.
Most of the heavy ships of the Kriegsmarine were used as commerce raiders in the early years of the war. Two of the panzerschiffe, Deutschland and Graf Spee, were already at sea at the outbreak of war; the former found little success and the latter was ultimately trapped and forced to scuttle after the Battle of the River Plate in December 1939. Hood but was herself sunk three days later. The loss of Bismarck led Hitler to prohibit further sorties into the Atlantic; the remaining capital ships were concentrated in Norway for use as a fleet in being and to threaten convoys to the Soviet Union on the Murmansk Run.From October 1940 to March 1941, Admiral Scheer went on her own raiding operation and captured or sank seventeen ships, which made her the most successful of the German capital ship surface raiders in the entire war. Scharnhorst and Gneisenau conducted Operation Berlin, a major sortie into the Atlantic in early 1941. Bismarck and Prinz Eugen went on the last Atlantic raiding mission, Operation Rheinübung, in May 1941. Bismarck sank the British battlecruiser HMS
Despite the fact that Plan Z produced no new warships in time for World War II, the plan represented the strategic thinking of the Oberkommando der Marine (OKM—"Naval High Command") at the time. Most significantly, the OKM favored surface combatants over the U-boats Dönitz needed for his submarine campaign in the North Atlantic, which left him with only a handful of submarines at the start of war. The two Scharnhorst-class battleships cost close to 150 million Reichsmarks apiece, and the two Bismarck-class ships cost nearly 250 million Reichsmarks each; for this amount of money, the Germans could have built more than a hundred additional Type VII U-boats. The shift to the submarine war was not definitively made until 1943, by which time the campaign had already been lost.
The Kriegsmarine was the navy of Nazi Germany from 1935 to 1945. It superseded the Imperial German Navy of the German Empire (1871–1918) and the inter-war Reichsmarine (1919–1935) of the Weimar Republic. The Kriegsmarine was one of three official branches, along with the Heer and the Luftwaffe of the Wehrmacht, the German armed forces from 1933 to 1945.
Bismarck was the first of two Bismarck-class battleships built for Nazi Germany's Kriegsmarine. Named after Chancellor Otto von Bismarck, the ship was laid down at the Blohm & Voss shipyard in Hamburg in July 1936 and launched in February 1939. Work was completed in August 1940, when she was commissioned into the German fleet. Bismarck and her sister ship Tirpitz were the largest battleships ever built by Germany, and two of the largest built by any European power.
Prinz Eugen was an Admiral Hipper-class heavy cruiser, the third of a class of five vessels. She served with Nazi Germany's Kriegsmarine during World War II. The ship was laid down in April 1936, launched in August 1938, and entered service after the outbreak of war, in August 1940. She was named after Prince Eugene of Savoy, an 18th-century Austrian general. She was armed with a main battery of eight 20.3 cm (8.0 in) guns and, although nominally under the 10,000-long-ton (10,000 t) limit set by the Anglo-German Naval Agreement, actually displaced over 16,000 long tons (16,000 t).
The Yamato-class battleships were two battleships of the Imperial Japanese Navy (IJN), Yamato and Musashi, laid down leading up to World War II and completed as designed. A third hull laid down in 1940 was converted to an aircraft carrier, Shinano, during construction.
The Scharnhorst class were the first capital ships, referred to as either battleships or battlecruisers, built for Nazi Germany's Kriegsmarine after World War I. The class comprised two vessels: Scharnhorst and Gneisenau. Scharnhorst was launched first, and is considered to be the lead ship by some sources; they are also referred to as the Gneisenau class in some other sources, as Gneisenau was the first to be laid down and commissioned. They marked the beginning of German naval rearmament after the Treaty of Versailles. The ships were armed with nine 28 cm (11 in) SK C/34 guns in three triple turrets; plans to replace these with six 38 cm (15 in) SK C/34 guns in twin turrets were never realized.
The Deutschland class was a series of three Panzerschiffe, a form of heavily armed cruiser, built by the Reichsmarine officially in accordance with restrictions imposed by the Treaty of Versailles. The ships of the class, Deutschland, Admiral Scheer and Admiral Graf Spee, were all stated to displace 10,000 long tons (10,000 t) in accordance with the Treaty, though they actually displaced 10,600 to 12,340 long tons at standard displacement. Despite violating the weight limit, the design for the ships incorporated several radical innovations to save weight. They were the first major warships to use welding and all-diesel propulsion. Due to their heavy armament of six 28 cm (11 in) guns and lighter weight, the British began referring to the vessels as "pocket battleships". The Deutschland-class ships were initially classified as Panzerschiffe but the Kriegsmarine reclassified them as heavy cruisers in February 1940.
Design B-65 was a class of Super Type A cruisers planned by the Imperial Japanese Navy (IJN) before and during World War II. As envisioned by the IJN, the cruisers were to play a key role in the Night Battle Force portion of the "Decisive battle" strategy which Japan hoped, in the event of war, to employ against the United States Navy.
The O class was a planned class of three battlecruisers for the Kriegsmarine before World War II. Prompted by a perceived lack in ship numbers when compared with the British Royal Navy, the O class' design was born with the suggestion of modifying the P-class cruiser design with 380 mm (15 in) guns instead of 283 mm (11.1 in).
The P class was a planned group of twelve heavy cruisers of Nazi Germany's Kriegsmarine; they were the successor to the Deutschland-class cruisers. Design work began in 1937 and continued until 1939; at least twenty designs were submitted with nine of them being considered. There were three designs that were selected as the final contenders. One design was armed with six 283mm main guns in one triple turret forward and one more turret aft. It had two 150mm double secondary gun turrets as secondary armament with one being positioned above and just fore of the aft of the main 283mm main turret, and the other being in front and lower of the front main gun turret. This design had more beam than the other 2 designs. It also mounted 2 seaplanes on its fantail instead of the mid ship area. The final design was armed with six 28 cm (11 in) quick-firing guns in two triple turrets, as in the preceding Deutschland class. The ships were designated as Panzerschiff, and given the preliminary names P1–P12. They were an improved design over the preceding planned D-class cruisers, which had been canceled in 1934. Although the ships were already assigned to shipyards, construction never began on the P-class ships after the O-class battlecruiser design superseded them.
The D-class cruisers were a pair of German cruisers, classified as Panzerschiffe by the Kriegsmarine. The ships were improved versions of the preceding Deutschland-class cruisers, authorized by Adolf Hitler in 1933. They were intended to counter a new French naval construction program. Displacement increased to 20,000 long tons (20,000 t), but Hitler allowed only increases to armor, prohibiting additions to the ships' main battery. Only one of the two ships was laid down, but it was canceled less than five months after the keel was laid. It was determined that the designs should be enlarged to counter the new French Dunkerque-class ships. The construction contracts for both ships were superseded by the Scharnhorst-class battleships.
The Bismarck class was a pair of fast battleships built for Nazi Germany's Kriegsmarine shortly before the outbreak of World War II. The ships were the largest and most powerful warships built for the Kriegsmarine; displacing more than 41,000 metric tons normally, they were armed with a battery of eight 38 cm (15 in) guns and were capable of a top speed of 30 knots. Bismarck was laid down in July 1936 and completed in September 1940, while her sister Tirpitz's keel was laid in October 1936 and work finished in February 1941. The ships were ordered in response to the French Richelieu-class battleships and they were designed with the traditional role of engaging enemy battleships in home waters in mind, though the German naval command envisioned employing the ships as long-range commerce raiders against British shipping in the Atlantic Ocean. As such, their design represented strategic confusion that dominated German naval construction in the 1930s.
The H class was a series of battleship designs for Nazi Germany's Kriegsmarine, which were intended to fulfill the requirements of Plan Z in the late 1930s and early 1940s. The first variation, "H-39," called for six ships to be built, essentially as enlarged Bismarck-class battleships with 40.6 cm (16.0 in) guns and diesel propulsion. The "H-41" design improved the "H-39" ship with still larger main guns, eight 42 cm (16.5 in) weapons, and reinforced deck armor. The Construction Office of the Oberkommando der Marine (OKM) concluded their work with the "H-41" design, and were not involved in subsequent plans. Two of them, "H-42" and "H-43", increased the main battery yet again, with 48 cm (18.9 in) pieces, and the enormous "H-44" design ultimately resulted with 50.8 cm (20.0 in) guns. The ships ranged in size from the "H-39", which was 277.8 m long on a displacement of 56,444 t, to the "H-44", at 345 m on a displacement of 131,000 t. Most of the designs had a proposed top speed in excess of 30 knots (56 km/h).
Tirpitz was the second of two Bismarck-class battleships built for Nazi Germany's Kriegsmarine (navy) prior to and during the Second World War. Named after Grand Admiral Alfred von Tirpitz, the architect of the Kaiserliche Marine, the ship was laid down at the Kriegsmarinewerft Wilhelmshaven in November 1936 and her hull was launched two and a half years later. Work was completed in February 1941, when she was commissioned into the German fleet. Like her sister ship Bismarck, Tirpitz was armed with a main battery of eight 38-centimetre (15 in) guns in four twin turrets. After a series of wartime modifications she was 2000 tonnes heavier than Bismarck, making her the heaviest battleship ever built by a European navy.
The Jade class comprised a pair of passenger ships intended to be converted into auxiliary aircraft carriers by Nazi Germany's Kriegsmarine during World War II. The two ships were launched as Gneisenau and Potsdam in 1935 and operated in peacetime by Norddeutscher Lloyd. After the outbreak of war, the ships were requisitioned by the Kriegsmarine as transports, and in May 1942, plans were drawn up to convert them into aircraft carriers. The ships were not identical, but were similar enough in size to allow identical outfitting.
Erich Johann Albert Raeder was a naval leader in Germany before and during World War II. This article covers Raeder's life as the Großadmiral up to the start of World War II. Raeder attained this naval rank, the highest possible, in 1939, becoming the first person to hold that rank since Alfred von Tirpitz. Raeder led the Kriegsmarine for the first half of the war; he resigned in 1943 and was replaced by Karl Dönitz. He was sentenced to life in prison at the Nuremberg Trials, but was released early due to failing health. Raeder is also well known for dismissing Reinhard Heydrich from the Reichsmarine in April 1931 for "conduct unbecoming to an officer and a gentleman".