who was this duke ?
William I was the first Norman King of England, reigning from 1066 until his death in 1087.
William the Conqueror
William I (c. 1028 – 9 September 1087), usually known as William the Conqueror and sometimes William the Bastard, was the first Norman King of England, reigning from 1066 until his death in 1087. 
who was the individual and what happened at this battle It was fought between the Norman-French army of William (the Duke of Normandy), and an English army under the Anglo-Saxon King Harold Godwinson, beginning the Norman conquest of England. what was the aftermath of this battle ? The day after the battle, Harold's body was identified. The bodies of the English dead, including some of Harold's brothers and housecarls, were left on the battlefield, although some were removed by relatives later. The Norman dead were buried in a large communal grave, which has not been found. Exact casualty figures are unknown. what was this battle called ? Battle of Hastings which location did it take place at  ? Northwest of Hastings, close to the town of Battle, East Sussex in England when di it take place ? 14 October 1066 who won this battle ? Norman-French army of William (the Duke of Normandy)
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William the Conqueror [SEP] Introduction
He decisively defeated and killed Harold at the Battle of Hastings on 14 October 1066. After further military efforts, William was crowned king on Christmas Day, 1066, in London. He made arrangements for the governance of England in early 1067 before returning to Normandy. Several unsuccessful rebellions followed, but William's hold was mostly secure on England by 1075, allowing him to spend the majority of his reign in continental Europe.