William V, Marquess of Montferrat

William V of Montferrat also known regnally as William III of Montferrat while also referred to as William the Old or William the Elder, in order to distinguish him from his eldest son, William Longsword, was seventh Marquis of Montferrat from 1135 to his death in 1191. William was the only son of Marquis Renier I and his wife Gisela, a daughter of Count William I of Burgundy and widow of Count Humbert II of Savoy. It seems likely, given that he was still fit enough to participate in battle in 1187, that William was one of his parents' youngest children.