Blücher

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.

Blücher was commissioned in September 1939 but entered Operation Weserübung before completing a full program of trials and training. As flagship of the force bound for Oslo, she carried troops and government personnel into the Oslofjord on 9 April 1940. Coastal guns and torpedoes at the Drøbak Narrows set the cruiser ablaze and caused her to capsize and sink only hours into her first combat operation. Her loss delayed the German occupation of Oslo and allowed the Norwegian government and royal family to escape the capital.