Briwere participated in the Sixth Crusade as a proxy for his uncle, who died before he was able to fulfill his crusading vows. The elder Briwere had taken the cross in 1189, but was excused temporarily because of his administrative duties. The nephew had released for his use 4000 marks that had been deposited with the Templars in the Holy Land by his uncle. Briwere went on the crusade with Peter des Roches, who was Bishop of Winchester. An army of other crusaders accompanied them to the East, although whether they were English or mercenaries recruited on the Continent is unclear. The contingent left from Brindisi in August 1227.