On 13 December at 05:20, the British squadron was proceeding on a course of 060° at 14 knots with
Ajax at , east of Montevideo. At 06:10, smoke was sighted on a bearing of Red-100, or 320° (to the north-west). Harwood ordered the
Exeter to investigate. She swung out of line, and at 06:16, she signaled by lamp: "I think it is a pocket-battleship". Captain Bell ordered Flag N hoisted to the yard arm – "Enemy in sight".
Graf Spee had already sighted mastheads and identified
Exeter but initially suspected that the two light cruisers were smaller destroyers and that the British ships were protecting a merchant convoy, the destruction of which would be a major prize. Since
Graf Spees reconnaissance aircraft was out of service, Langsdorff relied on his lookouts for that information. He decided to engage despite having received a broadly accurate report from the German naval staff on 4 December. It outlined British activity in the River Plate area and included information that
Ajax,
Achilles,
Cumberland and
Exeter were patrolling the South American coast. Langsdorff realised too late that he was facing three cruisers.
Graf Spee opened fire on
Exeter at with her six guns at 06:18.
Exeter opened fire at 06:20,
Achilles at 06:21,
Exeters aft guns at 06:22 and
Ajax at 06:23. Lieutenant-Commander Richard Jennings,
Exeters gunnery officer remembers: As I was crossing the compass platform [to his Action Station in the Director Control Tower], the captain hailed me, not with the usual rigmarole of "Enemy in sight, bearing, etc", but with "There's the fucking
Scheer! Open fire at her!" Throughout the battle the crew of the
Exeter thought they were fighting the [sister ship]
Scheer. But the name of the enemy ship was of course the
Graf Spee. From her opening salvo,
Graf Spee's gunfire proved fairly accurate, her third salvo straddling
Exeter. At 06:23, a
shell burst just short of
Exeter, abreast the ship. Splinters from the shell killed the torpedo tubes' crews, damaged the ship's communications, riddled the ship's funnels and searchlights and wrecked the ship's
Walrus aircraft just as it was about to be launched for gunnery spotting. Three minutes later,
Exeter suffered a direct hit on her "B" turret, putting it and its two guns out of action. Shrapnel swept the bridge, killing or wounding all bridge personnel except the captain and two others. Captain Bell's communications were wrecked. Communications from the
aft conning position were also destroyed. The ship had to be steered via a chain of messengers for the rest of the battle. Meanwhile,
Ajax and
Achilles closed to and started making in front of
Graf Spee, causing her to split her main armament at 06:30 and otherwise use her guns against them. Shortly after,
Exeter fired two
torpedoes from her
starboard tubes but both missed. At 06:37,
Ajax launched her
Fairey Seafox spotter
floatplane from her
catapult. At 06:38,
Exeter turned so that she could fire her
port torpedoes and received two more direct hits from shells. One hit "A" turret and put it out of action, the other entered the hull and started fires.
Exeter was severely damaged, having only "Y" turret still in action under "local" control, with Jennings on the roof shouting instructions to those inside. She also had a 7°
list, was being flooded and being steered with the use of her small boat's
compass. However,
Exeter dealt the decisive blow; one of her 8-inch shells had penetrated two decks before exploding in
Graf Spees funnel area, destroyed her raw fuel processing system and left her with just 16 hours fuel, insufficient to allow her to return home. At this point, nearly one hour after the battle had started,
Graf Spee was doomed since she could not make fuel system repairs of that complexity under fire. Two thirds of her anti-aircraft guns were knocked out, as well as one of her secondary turrets. There were no friendly naval bases within reach or reinforcements available. She was not seaworthy and could make only the neutral port of Montevideo.
Graf Spee hauled round from an easterly course, now behind
Ajax and
Achilles, towards the north-west and
laid smoke. That course brought Langsdorff roughly parallel to
Exeter. By 06:50,
Exeter listed heavily to starboard and took water forward. Nevertheless, she still steamed at full speed and fired with her one remaining turret. Forty minutes later, water splashed in by a near miss short-circuited her electrical system for that turret. Captain Bell was forced to break off the action. That would have been the opportunity to finish off
Exeter. Instead, the combined fire of
Ajax and
Achilles drew Langsdorff's attention as both ships closed the German ship. Twenty minutes later,
Ajax and
Achilles turned to starboard to bring all their guns to bear, causing
Graf Spee to turn away and lay a
smoke screen. At 07:10, the two light cruisers turned to reduce the range from even though that meant that only their forward guns could fire. At 07:16,
Graf Spee turned to port and headed straight for the badly damaged
Exeter, but fire from
Ajax and
Achilles forced her at 07:20 to turn and fire her guns at them, while they turned to starboard to bring all their guns to bear.
Ajax turned to starboard at 07:24 and fired her torpedoes at a range of , causing
Graf Spee to turn away under a smoke screen. At 07:25,
Ajax was hit by a shell that put "X" turret out of action and jammed "Y" turret, causing some casualties. By 07:40,
Ajax and
Achilles were running low on resources, and the British decided to change tactics and move to the east under a smokescreen. Harwood decided to shadow
Graf Spee and try to attack at night, when he could attack with torpedoes, better use his advantages of speed and manoeuvrability and minimise his deficiencies in armour.
Ajax was again hit by a shell that destroyed her mast and caused more casualties.
Graf Spee continued to the south-west. According to
Dudley Pope, a merchant ship was sighted at 11:03 close to
Admiral Graf Spee. After a few minutes,
Admiral Graf Spee called
Ajax on W/T, probably on the international watchkeeping frequency of 500 kHz, and used both ships' pre-war call signs, with the signal: "please pick up lifeboats of English steamer". The German call sign was DTGS, confirming to Harwood that the pocket-battleship he had engaged was indeed
Admiral Graf Spee.
Ajax did not reply, but a little later, the British flagship closed with SS
Shakespeare with her lifeboats still hoisted and men still on board.
Admiral Graf Spee had fired a gun and ordered them to stop but when they did not obey orders to leave the ship, Langsdorff decided to continue on his way, and
Shakespeare had a lucky escape. The shadowing continued for the rest of the day until 19:15, when
Admiral Graf Spee turned and opened fire on
Ajax, which turned away under a smokescreen. It was now clear that
Admiral Graf Spee was entering the River Plate estuary. Since the estuary had
sandbanks, Harwood ordered
Achilles to shadow
Admiral Graf Spee while
Ajax would cover any attempt to double back through a different channel. The sun set at 20:48, with
Admiral Graf Spee silhouetted against the sun.
Achilles had again closed the range and
Admiral Graf Spee opened fire, forcing
Achilles to turn away. During the battle, a total of 108 men had been killed on both sides, including 36 on
Admiral Graf Spee.
Admiral Graf Spee entered Montevideo in
neutral Uruguay and dropped anchor at about 00:10 on 14 December. That was a political error since Uruguay, while neutral, had benefited from significant British influence during its development and favoured the Allies. The
British Hospital, for example, where the wounded from the battle were taken, was the leading hospital in the city. The port of
Mar del Plata on the Argentine coast and south of Montevideo would have been a better choice for
Admiral Graf Spee.
Trap of Montevideo , with battle damage showing possible exit channels. In Montevideo, the 13th
Hague Convention came into play. Under Article 12, "belligerent war-ships are not permitted to remain in the ports, roadsteads or territorial waters of the said Power for more than twenty-four hours". Under Article 14, a "belligerent war-ship may not prolong its stay in a neutral port beyond the permissible time except on account of damage". British diplomats duly pressed for the speedy departure of the
Graf Spee. Also relevant was Article 16 of which part reads, "A belligerent war-ship may not leave a neutral port or roadstead until twenty-four hours after the departure of a merchant ship flying the flag of its adversary". In accordance with their obligations, the Germans released 61 captive British merchant seamen who had been on board. Langsdorff then asked the Uruguayan government for two weeks to make repairs. Initially, the British diplomats in Uruguay, principally
Eugen Millington-Drake, made several requests for
Admiral Graf Spee to leave port immediately. The crew of
Admiral Graf Spee were taken to
Buenos Aires,
Argentina, where Captain Langsdorff shot himself on 19 December. He was buried there with full military honours, and several British officers attended. Many of the crew members made their homes in Montevideo with the help of local people of German origin. The German dead were buried in the
Cementerio del Norte, Montevideo. == Aftermath ==