Battle of the River Plate between the German pocket battleship Admiral Graf Spee and the British cruisers Exeter, Ajax and Achilles. At the end of the fighting the Graf Spee sailed into the neutral port of Montevideo.
How to cite this article: Rickard, J (28 December 2007), 13 December 1939 , http://www.historyofwar.org/secondworldwar/date/1939_12_13.html