Arnaud Amaury

Arnaud Amaury (Latin: Arnoldus Amalricus; died 1225) was a Cistercian abbot who played a prominent role in the Albigensian Crusade. He is remembered for purportedly advising a soldier who was worried about killing Catholics instead of just heretic Cathars, prior to the sack of Béziers, to simply kill everyone, as God would sort it all out later.

He was abbot of Poblet in Catalonia from 1196 to 1198, then of Grandselve from 1198 to 1202. He then became the seventeenth abbot of Cîteaux (until 1212).

In 1204, he was named a papal legate and inquisitor and was sent by Innocent III with Peter of Castelnau and Arnoul to attempt the conversion of the Albigensians. Failing in this, he distinguished himself by the zeal with which he incited men by his preaching to the crusade against them. He was in charge of the crusader army that sacked Béziers in 1209. There, according to the Cistercian writer Caesarius of Heisterbach, Arnaud Amalric responded when asked by a Crusader how to distinguish the Cathars from the Catholics,

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