In 1939 the Graf Spee sank a number of merchant ships in the south Atlantic Ocean and Indian Ocean, with the first on September 30. The Allies formed seven hunting groups in the Atlantic and one in the Indian Ocean to look for her, totalling three battleships, four aircraft carriers, and 16 cruisers. More groups were assembled later.
On December 13 1939, she was found by the British Hunting Group G - the 8-inch gunned cruiser HMS Exeter, and 6-inch gunned light cruisers HMS Ajax and HMNZS Achilles - in the Battle of the River Plate. After taking relatively superficial damage and retreating to the neutral port of Montevideo, the ship was scuttled by Captain Hans Langsdorff to avoid risking the crew in what he thought would be a losing battle.