Sheriff George Of Nottingham is the main antagonist of Robin Hood: Prince Of Thieves.
He is portrayed by Alan Rickman who also played Hans Gruber.
Robin Hood: Prince Of Thieves
During the crusades, when Robin and the king are away, the Sheriff takes over England with the aid of his cousin, Guy of Gisbourne, Mortianna the witch, and the corrupt Bishop of Hereford. He murders Robin's father after he refuses to join the Sheriff and sets his sights on taking the throne by wedding and then impregnating Maid Marian (though it's heavily implied he had feelings for her even before trying to marry her for the throne). When Robin returns and joins the Sherwood outlaws, the Sheriff sends an army of Celts to raid, kill and capture the majority of them.
The Sheriff later forces Maid Marian to marry him and plans to hang the outlaws on the same day. Robin and a few of the other outlaws who managed to avoid capture travel to Nottingham and Robin engages the Sheriff in a sword fight. Eventually, Robin kills him with a dagger Maid Marian gave him, which ironically the Sheriff himself had given to her
It is implied several times in the film that the Sheriff is a devil worshiper (for which he had framed Lord Locksley of being). In the uncut version, this is explicitly shown and it is also revealed that the Sheriff is the son of Mortianna - that she had kidnapped and murdered the infant son of the man who Nottingham believed to be his father and replaced the infant with the Sheriff.