The Battle of Coronel was the worst British naval defeat of the First World War. At the start of the war the Germans had eight modern cruisers scattered around the world. Their role was to intercept and sink Allied shipping, causing as much disruption as possible. A powerful squadron soon formed under the command of Admiral Maximilian von Spee. He began with two ships – the Scharnhorst and the Gneisenau, based in the Caroline Islands. He was then joined by the Nürnberg, Leipzig and Dresden. This gave his a squadron of five modern cruisers, faster, better armoured and better armed than any British ships then in the Pacific or South Atlantic. A small number of battlecruisers (lightly armoured but otherwise similar to the dreadnaughts of the main battle fleet) had been built but at the start of the war the battlecruisers were with the Grand Fleet, facing the German High Seas Fleet in the North Sea.
Von Spee had not had a profitable time in the Pacific. Japan had entered the war on the Allied side, and her powerful fleet made the north Pacific too dangerous for von Spee. After a period spent attacking French possessions in the south Pacific, von Spee decided to move his squadron into the South Atlantic.
News of his plans soon reached the British. Radio messages between his ships were intercepted and the German code broken. The British commander in the South Atlantic, Admiral Christopher Cradock, decided to intercept von Spee while he was still in the Pacific, and took his small squadron through the Straits of Magellan into Chilean waters. This was a bold but foolhardy move. Cradock simply did not have the ships to face von Spee. His fleet consisted of the battleship Canopus, built in 1896, and too slow to catch up with his cruisers. His main strength consisted of the cruisers Monmouth and Good Hope and the light cruiser Glasgow. He also had a converted merchantman, the Otranto, which took no part in the battle.
Once in the Pacific, Cradok sent the Glasgow ahead to the port of Coronel. By this point Cradock believed that von Spee's strongest ships were heading away from him. British radio security was not much better than German, and Spee soon learnt of Glasgow’s presence in the port and the imminent arrival of the Monmouth and Good Hope. The two British cruisers reached Coronel on the evening of 1 November. Von Spee waited until nightfall and then opened fire on the British squadron.
Cradok was badly outgunned. The Gneisenau and Scharnhorst each had eight 8.2in guns. In contrast, HMS Good Hope carried two 9.2in guns and sixteen 6in guns, while HMS Monmouth was armed with fourteen rapid firing 6in guns. Von Spee was able to stand outside the range of all but two of Cradok’s guns and pound the British ships.
After a short fight the Good Hope and Monmouth were both sunk, with the loss of all 1,600 crewmen. The Glasgow was able to escape to warn the Canopus.
The Battle of Coronel was the first British defeat at sea since the War of 1812. The reaction in Britain was understandably extreme. The new First Sea Lord, Admiral Sir John Fisher, organised a massive hunt for von Spee’s squadron, involving elements of the Royal Navy and the Japanese fleet. Two of the precious battlecruisers, HMS Invincible and Inflexible, were dispatched to the South Atlantic, where on 8 December they encountered and destroyed von Spee’s fleet (Battle of the Falklands).