William fitz Duncan

William fitz Duncan (a modern anglicisation of the Old French Guillaume fils de Duncan and the Middle Irish Uilleam mac Donnchada) was a Scottish prince, the son of King Duncan II of Scotland by his wife Ethelreda of Dunbar. He was a territorial magnate in northern Scotland and northern England and a military leader. In 1094, his father King Duncan II was killed by Mormaer Máel Petair of Mearns, supporting the claims of King Domnall (Donald) III Bán. It is probable that his mother Ethelreda took the infant William and fled Scotland to the safety of Allerdale in Cumberland where her brother Waltheof of Allerdale was lord. William, an only child, grew up there among his cousins. A decade or so later, he ventured to the court of his half-uncle. Under the reign of his half-uncle Alexander I, it is highly likely that William was regarded as a viable tánaiste (i.e. "designated heir"), but Henry I of England supported David. When David succeeded, William, as the legitimate king under the rules of primogeniture was certainly bought off by David, probably being made tánaiste. William repeatedly leads the lists of witnesses appearing in Scottish royal charters in the reigns of Alexander I and David I. A 13th century northern English source claims that William was Mormaer of Moray. As this source had no reason to deceive, it is highly likely that William was made the ruler of Moray after the defeat of King Óengus of Moray in 1130. It is feasible that this grant had something to do with the coming of age of David's son, Prince Henry and may also be a factor in his marriage to a daughter of Óengus. As well as being the ruler of Moray, William controlled the English lands of Allerdale, Skipton and Craven, making him one of the greatest barons of northern England.