Willam Stark was a member of House Stark and a former Lord of Winterfell. He was the oldest son of Lord Beron Stark and older brother of Artos the Implacable. He is buried in the crypts of Winterfell.
He married two times, first with Lyanne Glover, then with Melantha Blackwood . In his first marriage he had one son, Brandon, in his second he had one son and one daughter. His son was Edwyle Stark, the grandfather of Eddard Stark. His daughter Jocelyn married to Benedict of House Royce.
When Raymun Redbeard went over the Wall, Lord Willam Stark called his banners and marched north with Lord Harmond Umber. On the shores of Long Lake, the two forces met. During the Battle of Long Lake, Willam was killed and beheaded. His younger brother Artos avenged him by slaying Raymun.