Battle of Hastings (1066)

On 14 October 1066, William the Conqueror's Norman forces defeated King Harold II — who died with an arrow through his eye according to the Bayeux Tapestry — and permanently altered the trajectory of English history. The conquest introduced Norman-French vocabulary into Old English, creating the hybrid language that became modern English. It replaced Anglo-Saxon aristocracy with French-speaking lords, transforming England's legal, cultural, and political institutions from the ground up. The Domesday Book, feudalism, and the foundations of English common law all trace directly to this single afternoon's fighting.