He was only eleven when his father died in September 1298 from wounds he received at the Battle of Furnes on 20 August 1297 against the Flemish people. The early death of his father was an indirect cause of the dispute over the succession to the County of Artois. After the death of his grandfather Robert II, Count of Artois, in the Battle of Courtrai in 1302, his grandfather's daughter Mahaut of Artois, inherited the County of Artois, in accordance with custom, for she was his eldest child. Because of his age, Robert III could not object to his aunt Mahaut and assert the rights which he inherited from his father. He would do so later. The rancor and intrigues between Mahaut (sometimes called Mathilde) and Robert occurred within a period of strife between France and England, before the Hundred Years' War.