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who said shoot them all and let god sort them out
Prior to the massacre of Béziers, it was reported that Arnaud Amalric, when asked how to distinguish Cathars from Catholics, responded, Kill them all! God will know his own.“
who was anraud amalric
Arnaud Amalric was a Roman Catholic Cistercian abbot who played a prominent role in the Albigensian Crusade.
what was the albigemsian crusade
The Albigensian Crusade or the Cathar Crusade was a 20-year military campaign initiated by Pope Innocent III to eliminate Catharism in Languedoc, in southern France.

Question: what was the religion
Self-contained rewrite: what was catharism