The Crusade Against Christians.

Some 2,500 years ago, the Greek dramatist Aeschylus said: “In war, truth is the first casualty.” History has been bearing him out ever since, as it did early in the year 1208. Europe was in turmoil, as impoverished rural residents sought their fortune in the rapidly growing cities. But there they found only more poverty. The building social upheaval would result in the emergence of a large Christian sect calling themselves the Cathars, from the Greek word for “pure,” katharos. Others called them the Albigensians for their association with the southern French commune of Albi.

Despite the new group’s extreme asceticism (they rejected the corruption and excesses plaguing the Roman Catholic Church), Catharism became a popular religion in southern France and northern Italy. Upon realizing the popularity of the movement, Pope Innocent III became deeply concerned about this threat to his papacy, seeing it as a potential religious revolution that might go so far as to undermine the power of the established Church. The pope ordered The count of Toulouse, Raymond VI, to suppress the heretical sect; however then the papal legate was murdered, and Raymond was accused of having ordered the killing. This lead the pope to try to eliminate the threat posed by the Cathars by proclaiming a crusade against them.

Thus he sent an army to massacre the people of Provence, who included Cathars and Catholics.It was unheard of for a pope to break such a signifi cant taboo by calling for the death of members of his own faith. Even so, the next papal legate, Arnaud Amaury, said this when asked how to distinguish Cathars from Catholics: “Kill them all! God will know His own.”

The pope’s knights obeyed, acting with methodical brutality. The legate gave this account of the massacre in Béziers in July 1209. “Our men spared no one—irrespective of rank, sex, or age—and put to the sword almost 20,000 people.” This deadly violence of Christian against Christian lasted for two decades. As the Albigensian Crusade came to an end, the Papal Inquisition was initiated to apprehend heretics, including remaining Cathars, who’d been forced underground.

By the end of that century the Cathars’ hierarchy had faded, though pockets of resistance lingered for 100 years before vanishing in the 15th century. Raphael Lemkin, who coined the term “genocide,” called the Albigensian Crusade “one of the most conclusive cases of genocide in religious history.”