Robert of Cassel

Robert of Cassel (c. 1278–1331), second son of Count Robert III of Flanders, held Cassel and Dunkirk, receiving maritime Flanders as an apanage in 1320. Unlike his elder brother Louis of Nevers, he backed his father in the wars with Philip IV. He built a castle at Dunkirk around 1322, but it was demolished during a Flemish revolt.

After the rebels were crushed at the Battle of Cassel in 1328, he fined them heavily, restoring Dunkirk's customs and rights a year later. He died at Warneton in 1331, leaving young children.