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