The first count of Guelders was Gerard IV, Lord of Wassenberg.
During Reinoud II's reign, the county of Guelders was elevated to a duchy.
After the death of Reginald III without issue, two of his sisters disputed the succession of the Duchy of Guelders:
Arnold sold the Duchy of Guelders to Charles I, Duke of Burgundy, who was recognized by the Holy Roman Emperor as Duke of Guelders.
The Egmond family did not abandon their claims to Guelders and Charles of Egmond conquered the Duchy in 1492. He remained in power with support of the French king.
William Thatcher, the lead character in the 2001 film A Knight's Tale played by Heath Ledger claimed to be Sir Ulrich von Liechtenstein from Gelderland so as to appear to be of noble birth and thus qualify to participate in jousting.