Renaud de Montmirail was a French noble linked to the Champagne region who was a member of the Fourth Crusade and a prominent opponent of diverting it to attack Constantinople. He was a younger son of Jean de Montmirail (1165-1217), a very prominent French feudal lord and Constable of France. As part of the dissenting faction that refused to attack Constantinople, Renaud successfully reached the Middle East, and died on the crusade.
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Renaud de Montmirail Wikipedia(Text) CC BY-SA