The Guelders War of Succession was a battle for the throne of the Duchy of Guelders that raged between 1371 and 1379.
The war originated when Duke Rainald III died without issue in 1371. His brother, Edward, who had been killed in the Battle of Baesweiler earlier that same year also left no offspring. The pretenders to the ducal throne were the two daughters of Duke Rainald II: Mathilde, who was married to John II, Count of Blois, and Maria, wife of William II of Jülich and mother to William I of Guelders and Jülich, on whose behalf she claimed the throne of Guelders.
14th-century Guelders was divided in two factions. The Heeckerens supported Machteld, and the Bronkhorsters supported William. The war lasted eight years, with Maria and her supporters emerging victorious and Maria's son William, becoming Duke of Guelders.