The Deutschland class was a series of three Panzerschiffe (armored ships), 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 (10,770 to 12,540 t) at standard displacement. The design for the ships incorporated several radical innovations, including the first major use of welding in a warship 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.

The three ships were built between 1929 and 1936 by the Deutsche Werke in Kiel and the Reichsmarinewerft in Wilhelmshaven, seeing much service with the German Navy. All three vessels served on non-intervention patrols during the Spanish Civil War. While on patrol, Deutschland was attacked by Republican bombers, and in response, Admiral Scheer bombarded the port of Almera. In 1937, Admiral Graf Spee represented Germany at the Coronation Review for Britain's King George VI. For the rest of their peacetime careers, the ships conducted a series of fleet maneuvers in the Atlantic and visited numerous foreign ports in goodwill tours.

Before the outbreak of World War II, Deutschland and Admiral Graf Spee were deployed to the Atlantic to put them in position to attack Allied merchant traffic once war was declared. Admiral Scheer remained in port for periodic maintenance. Deutschland was not particularly successful on her raiding sortie, during which she sank or captured three ships. She then returned to Germany, where she was renamed Ltzow. Admiral Graf Spee sank nine vessels in the South Atlantic before she was confronted by three British cruisers at the Battle of the River Plate. Although she damaged the British ships, she was herself damaged and her engines were in poor condition. Coupled with deceptive false British reports of reinforcements, the state of the ship convinced Hans Langsdorff, her commander, to scuttle the ship outside Montevideo, Uruguay.

Ltzow and Admiral Scheer were deployed to Norway in 1942 to join the attacks on Allied convoys to the Soviet Union. Admiral Scheer conducted Operation Wunderland in August 1942, a sortie into the Kara Sea to attack Soviet merchant shipping, though it ended without significant success. Ltzow took part in the Battle of the Barents Sea in December 1942, a failed attempt to destroy a convoy. Both ships were damaged in the course of their deployment to Norway and eventually returned to Germany for repairs. They ended their careers bombarding advancing Soviet forces on the Eastern Front; both ships were destroyed by British bombers in the final weeks of the war. Ltzow was raised and sunk as a target by the Soviet Navy, and Admiral Scheer was partially broken up in situ, with the remainder of the hulk buried beneath rubble.



An armed merchantman is a merchant ship equipped with guns, usually for defensive purposes, either by design or after the fact. In the days of sail, piracy and privateers, many merchantmen would be routinely armed, especially those engaging in long distance and high value trade.

In more modern times, auxiliary cruisers were used offensively as merchant raiders to disrupt trade chiefly during both World War I and World War II, particularly by Germany.

While armed merchantmen are clearly inferior to purpose-built warships, sometimes they have scored successes in combat against them. Examples include East Indiamen mimicking ships of the line and chasing off regular French warships in the Battle of Pulo Aura in 1804, and the German auxiliary cruiser Kormoran sinking the Australian light cruiser HMAS Sydney in their battle in 1941, although Kormoran was also destroyed and had to be scuttled.