In April 1066, Haley's Comet passed over England, causing mass panic. Many believed it to be a warning of a powerful force that would bring cataclysmic change. Later that year, William the Conqueror would wreak havoc on England. The Normans, descendants of Vikings, established themselves as a distinct race in Normandy. The Duke of Normandy, later called William The Conqueror, sought to spread Norman control and seize the English throne.