First War of the Guelderian Succession

The First War of the Guelderian Succession was a battle for the throne of the Duchy of Guelders that raged between 1371 and 1379.

First War of the Guelderian Succession
Date 1371-1379 Location Duchy of Guelders Result Victory of William of Jülich
Belligerents
Duchy of Jülich Bronckhorst faction	Blois Heeckeren faction
Commanders and leaders
William III Mary of Guelders	John II of Blois Machteld of Guelders

The war originated when Duke Reginald 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 claimants to the ducal throne were their half-sisters: Matilda, 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 Matilda, and were led by Frederik van Heeckeren van der Eze (1320-1386).
• The Bronckhorsters supported William, and were led by Gijsbert V van Bronckhorst (1328-1356).

The war lasted eight years, with Maria and her supporters emerging victorious, and Maria's son William becoming duke.