He gives an account of the barons' war from a royalist standpoint, and is a severe critic of Montfort's policy.
In 1265, after Montfort's fall, Edmund received the earldom of Leicester, and two years later was created earl of Lancaster.
At Amiens in 1264; he was made chancellor of England in February 1265, but was deprived of this office after Montfort's death at Evesham, and lived out of England for some time.
In 1211 the boy was entrusted to Montfort's care to be educated, but the aggressions of the crusaders on the princes of the south forced Peter to take up arms against them, and he was slain at Muret on the 12th of September 1213.
The church preached Simon de Montfort's crusade, and organized Dominic's Inquisition; what Quinet calls the "Renaissance sociale par l'Amour" was extirpated by sword, fire, famine and pestilence.