Ranulf Flambard was a medieval Norman Bishop of Durham and an influential government minister of King William Rufus of England. Ranulf was the son of a priest of Bayeux, Normandy, and his nickname Flambard means incendiary or torch-bearer, and may have referred to his personality. He started his career under King William I of England, probably in the compilation of the Domesday Book of 1086, as well as being the keeper of the king's seal. On the death of William I, Ranulf chose to serve the new king of England, William Rufus.

William II was King of England from 26 September 1087 until his death in 1100, with powers over Normandy and influence in Scotland. He was less successful in extending control into Wales. The third son of William the Conqueror, he is commonly referred to as William Rufus, perhaps because of his ruddy appearance or, more likely, due to having red hair.