William I, Count of Nevers (French: Guillaume Ier, c. 1029 – 20 June 1100), was the son of Renauld I, Count of Nevers and Hedwig of France, Countess d'Auxerre.[1] He married Ermengarde, daughter of Renauld, Count of Tonnerre about 1039.[1] William died in 1098.[1]