He was an important ally of Simon de Montfort during the reign of Henry III. He served briefly as Justiciar of England in 1260 and as Constable of the Tower of London.
Hugh Le Despenser, chief justiciar of England, first plays an important part in 1258, when he was prominent on the baronial side in the Mad Parliament of Oxford. In 1260 the barons choose him to succeed Hugh Bigod as Justiciar, and in 1263 the king was further compelled to put the Tower of London in his hands.
He was the son of Hugh le Despenser I and was summoned to Parliament by Simon de Montfort Hugh was summoned as Lord Despencer Dec. 14, 1264 and was Chief Justiciar of England and a leader of the baronial party, and so might be deemed a baron, though the legality of that assembly is doubtful. He remained allied with Montfort to the end, and was present at the Battle of Lewes. He was killed fighting on de Montfort's side at the Battle of Evesham in August, 1265. He was slain by Roger Mortimer, 1st Baron Wigmore; this caused a feud to begin between the Despenser and Mortimer families.
By his wife, Aline Bassett, he was father of Hugh the elder Despenser. She was the daughter of Philip Basset, who had also served as Justiciar.
Hugh le Despenser, 1st Lord le Despenser 
