During the civil war in Holland and Hainaut (which is in a personal union with Holland) in 1350 between the Hooks and the Cods, the Hooks are fighting for the Countess Margaret of Hainaut, supported by England, while the Cods are fighting for Margaret's son William, who is ruling Holland in name of Margaret.
William defeats the Hooks and the English in the Battle of Vlaardingen in 1351.
