Seydlitz

The Admiral Hipper class emerged from Germany's return to heavy-cruiser construction in the 1930s. Although conceived within the 10,000-ton, 20.3 cm-gun limits associated with the Washington treaty system, the completed ships were substantially larger than the nominal limit.

Five ships were laid down between 1935 and 1937. Admiral Hipper and Blücher formed the first group, while Prinz Eugen, Seydlitz and Lützow incorporated an improved design. Seydlitz and Lützow were initially considered as 15 cm-gun light cruisers, but both were reordered with 20.3 cm guns. The class was intended for commerce warfare, combining heavy armament with sufficient speed to avoid stronger opponents.

In practice, the ships' high-pressure steam machinery consumed too much fuel for sustained Atlantic operations and proved difficult to maintain. Only Admiral Hipper, Blücher and Prinz Eugen were completed as heavy cruisers; construction of Seydlitz and Lützow remained unfinished.

Seydlitz was launched in January 1939 but was never commissioned. Although construction had progressed far, work stopped during the war and plans were made to complete her through conversion into the auxiliary aircraft carrier Weser. The conversion began in 1942, with the main armament and much of the superstructure removed, but the project was abandoned the following year. The incomplete hull was transferred to Königsberg, used as an accommodation ship and scuttled as Soviet forces approached. Raised after the war and taken to Leningrad, Seydlitz was judged beyond economical repair and was ultimately scrapped in 1958.