William VIII

William VIII may refer to:


 * William VIII, Duke of Aquitaine (1025–1086)
 * William VIII of Montpellier (died 1202)
 * William VIII of Jülich, Count of Ravensberg (c. 1380–1428)
 * William VIII, Marquis of Montferrat (1420–1483)
 * William VIII, Landgrave of Hesse-Kassel (1682–1760)