Final answer:
William the Conqueror took possession of England after the Battle of Hastings in 1066, ending Anglo-Saxon rule and beginning the Norman dynasty, significantly impacting English culture, language, and politics.
Step-by-step explanation:
The individual who took possession of England after the decisive Battle of Hastings in 1066 was William the Conqueror. This marked the end of Anglo-Saxon rule and the beginning of Norman control over England.
Before William's conquest, England was primarily an Anglo-Saxon nation that had experienced various waves of invasions and settlements, notably by the Vikings. A kingdom in northern France, Normandy, was granted to the Viking king Rollo in 911, laying the groundwork for William's ancestry and future conquest. William, a descendant of these Vikings turned Norman dukes, invaded England and defeated King Harold II at the Battle of Hastings. This battle was a culmination of power struggles and claims to the English throne following the death of King Edward the Confessor, who left no clear heir.
Through this victory at Hastings, William established Norman rule in England, which led to significant cultural and linguistic changes, as well as shifts in the social and political structures of the country. William's rule also marked the integration of Norse and Frankish influences into English society.