Robert Jenkins was a Welshman and a sailor, who had his ear cut off by a Spaniard; Captain Julio Leon Fandino, who suspected Jenkins of smuggling. Captain Julio then suggested that Jenkins tell the King (George II) that the same would happen to him if he was caught doing the same.
As it happened Jenkins did exactly that and Captain Julio wasn't laughing so much when the King sent in the Navy. Bizarrely this was eight years after the ear chopping incident, in which time Jenkins had shown just about everybody else his ear (now pickled in a jar), including the House of Commons, who decided that the Spanish should not be allowed to get away with it.
Then followed several years of the British battering Spanish ports (across the whole Spanish empire, including most of the Caribbean) with mixed success. Spanish pirates did quite well out of it too by attacking British ships, which led to the British taking it out on French merchant vessels. The French, however, decided not to join the war, which was probably wise.
Later the British and the Spanish forgot all about it and after 1750 actually became quite friendly.
The only disappointment I have is that the Pickled Ear wasn't used as a sort of trophy, which could be handed over to whichever side was winning. On a happier note, though, the war is still commemorated annually ... in Savannah, Georgia.