The Cathar Crusade:Part II-Kill Them All

The Cathar Crusade, a crusade against non-violent followers of a different form of Christianity, lasted from 1209 to 1229, and resulted in the conquest of the Toulouse region by the French king, the establishment of papal domination over the Christian church in Europe and the creation of the Papal Inquisition, basically the first secret police. Part II examines the papacy's attempt to defeat the Cathars through public debate. When debate failed, Pope Innocent III seized on a flimsy excuse to declare a crusade against the residents of the Languedoc, threatening them with the loss of their lands if they did not abandon the Cathars.

Cast of Characters:
Simon de Montfort-Earl of Leicester, leader of the crusade 
Raymond VI-Count of Toulouse
Raymond Roger Trencavel-Viscount of Beziers and Carcasonne
Raymond-Roger-Count of Foix
Arnaud Almaric-Cistercian abbot, papal legate
Fulk-Bishop of Toulouse, member of the Cistercian Order
Innocent III-Pope
Pedro II-King of Aragon, count of Barcelona

Sources:
Kill Them All: Cathars and Carnage in the Albigensian Crusade-Sean McGlynn
The Occitan War: A Military and Political History of the Albigensian Crusade, 1209-1218-Laurence W. Marvin
A Most Holy War: The Albigensian Crusade and the Battle for Christendom-Mark Gregory Pegg
The Perfect Heresy: The Life and Death of the Cathars-Stephen O'Shea
The Albigensian Crusade-Jonathan Sumption
Pope Innocent III and His Times-Joseph Clayton
Innocent III: Leader of Europe 1198-1216-Jane Sayers
The Popes: A History-John Julius Norwich
The Medieval World: Europe 1100-1350-Friedrich Heer, translated by Janet Sondheimer

Image Credit:
Pope Innocent III excommunicating the Albigensians (left). Massacre against the Albigensians by the Crusaders (right). 
By Chroniques de Saint-Denis - http://www.bl.uk/catalogues/illuminatedmanuscripts/ILLUMIN.ASP?Size=mid&IllID=43733, Public Domain, https://commons.wikimedia.org/w/index.php?curid=13305991