Hugh was son of Gaucher III of Châtillon and Elisabeth, daughter of Hugo IV, Count of Saint-Pol.

[1] They had 5 children: Through his marriage Hugh became the first Count of Blois from the House of Châtillon.

After the death of Marie, Hugh married Mahaut, sister of Baldwin III, Count of Guînes.

[3] Later Hugh, with the assistance of Philip Mécringes, founded a Cistercian nunnery at Troissy called L'Amour-Dieu in 1232.

[3] Hugh intended to follow the pious king Louis IX when he started on the Seventh Crusade, but he died in 1248.