The first naval battle of World War II was the **Battle of the Atlantic**, which began almost immediately after the war started in September 1939. This protracted campaign involved the naval forces of the Allied powers, primarily Britain, against the German Kriegsmarine, with the primary aim being the control of vital shipping routes across the Atlantic Ocean. While specific skirmishes and engagements occurred early in the war, one of the first major naval actions was the **Battle of the River Plate** on December 13, 1939.
The Battle of the River Plate took place off the coast of Uruguay, near the mouth of the River Plate, and was a significant early engagement between the British Royal Navy and the German Navy. It involved a confrontation between the German pocket battleship **Admiral Graf Spee**, commanded by Captain Hans Langsdorff, and a force of three British cruisers: **HMS Ajax**, **HMS Achilles**, and **HMS Exeter**.
The *Graf Spee* had been raiding British merchant shipping in the South Atlantic, and the British sought to stop its operations. The three British cruisers engaged the German ship, with the *Graf Spee* suffering significant damage during the battle. After being hit by British fire, the *Graf Spee* withdrew to the neutral port of Montevideo, Uruguay, for repairs. The British, unaware of the extent of the damage, followed the German vessel.
Facing limited supplies and the threat of further attack, Captain Langsdorff decided to scuttle the *Graf Spee* on December 17, 1939, rather than risk its capture by the British. The battle was a significant victory for the Royal Navy, as it crippled a powerful German warship and marked the beginning of a long and hard-fought naval struggle for control of the Atlantic.
Thus, while there were earlier skirmishes, the **Battle of the River Plate** is considered the first major naval battle of World War II.