October 14, 1066: The Battle of Hastings — Anglo-Saxon King Harold Godwinson, having repulsed a Norwegian invasion under Harald Hardrada at Stamford Bridge (generally regarded as the end of the Viking Age; in which case the very last thing that happened in the Viking Age is the doomed Norwegian charge known to history as ‘Orre‘s Storm’) just two weeks before fares decidedly less well at Hastings, being shot in the face with an arrow.
Harold’s death in battle subsequently allowed for the ascension of William the Conqueror the throne of England and the subsequent establishment of Norman rule in England and the decline of the previous Anglo-Saxon culture, helped along by the fact that William killed off a lot of the Anglo-Saxon leadership. And populace in general.
So, basically, everyone historically notable was really a jerk.
Incidentally, “Norman Conquest” is going to be the name of my autobiography.