Editing Catharism (section)

=== Albigensian Crusade ===
{{main|Albigensian Crusade}}
[[File:Albigensian Crusade 01.jpg|thumb|upright=1.3|[[Pope Innocent III]] excommunicating the Albigensians (left), massacre of the Albigensians by the crusaders (right)]]

In January 1208, the papal legate, [[Pierre de Castelnau]], a [[Cistercian]] monk, theologian and canon lawyer, was sent to meet the ruler of the area, [[Raymond VI, Count of Toulouse]].{{sfnp|Sumption|1999|pp=68–69}} Known for excommunicating noblemen who protected the Cathars, Castelnau [[excommunication|excommunicated]] Raymond for [[abettor|abetting]] heresy, following an allegedly fierce argument during which Raymond supposedly threatened Castelnau with violence.{{sfnp|Sumption|1999|pp=72–73}} Shortly thereafter, Castelnau was murdered as he returned to Rome,<ref name="Madaule 1967"/> allegedly by a knight in the service of Count Raymond.<ref name="Belloc 1938 92"/> His body was returned and laid to rest in the [[Abbey of Saint-Gilles]].

As soon as he heard of the murder, the Pope ordered the [[Papal legate|legate]]s to preach a [[Albigensian Crusade|crusade]] against the Cathars,<ref name="Belloc 1938 92"/> and wrote a letter to [[Philip II of France|Philip Augustus, King of France]], appealing for his intervention—or an intervention led by his son, [[Louis VIII of France|Louis]]. This was not the first appeal, but some see the murder of the legate as a turning point in papal policy, which had hitherto refrained from the use of military force.<ref>{{harvnb|Belloc|1938|pp=89–91}}</ref> Raymond of Toulouse was excommunicated, the second such instance, in 1209.<ref name="Belloc 1938 92"/>

King Philip II of France refused to lead the crusade himself, and could not spare his son, Prince Louis VIII, to do so either—despite his victory against [[John, King of England]], as there were still pressing issues with Flanders and the empire along with the threat of an [[House of Châteaudun|Angevin]] revival. While King Philip II could not lead the crusade nor spare his son, he sanctioned the participation of some of his barons, notably [[Simon de Montfort, 5th Earl of Leicester|Simon de Montfort]]<ref name="Belloc 1938 92"/> and Bouchard de Marly. The twenty years of war against the Cathars and their allies in the Languedoc that followed were called the [[Albigensian Crusade]], derived from [[Albi]], the capital of the Albigensian district, the district corresponding to the present-day [[Tarn (department)|French department of Tarn]].<ref>{{harvnb|Belloc|1938|p=89}}</ref>

[[File:Carcasonneouterwall.jpg|thumb|upright=1.3|[[Cité de Carcassonne]] in 2007]]
This war pitted the nobles of France against those of the Languedoc. The widespread northern enthusiasm for the Crusade was partially inspired by a papal decree that permitted the confiscation of lands owned by Cathars and their supporters. This angered not only the lords of the south,<ref>{{harvnb|Belloc|1938|pp=92–93}}</ref> but also the King Philip II of France, who was at least nominally the [[Suzerainty|suzerain]] of the lords whose lands were now open to seizure. King Philip II wrote to Pope Innocent in strong terms to point this out—but Pope Innocent refused to change his decree. As the Languedoc was supposedly teeming with Cathars and Cathar sympathisers, this made the region a target for northern French noblemen looking to acquire new fiefs.{{citation needed|date=June 2021}}

The first target for the barons of the North were the lands of the [[Trencavel]], powerful lords of Carcassonne, Béziers, Albi, and the Razes. Little was done to form a regional coalition, and the crusading army was able to take Carcassonne, the Trencavel capital, incarcerating [[Raymond Roger Trencavel]] in his own citadel, where he died within three months. Champions of the [[Occitania|Occitan]] cause claimed that he was murdered. Simon de Montfort was granted the Trencavel lands by Pope Innocent, thus incurring the enmity of [[Peter II of Aragon]], who previously had been aloof from the conflict, even acting as a mediator at the time of the siege of Carcassonne.

The remainder of the first of the two Cathar wars now focused on Simon de Monfort's attempt to hold on to his gains through the winters. With a small force of confederates operating from the main winter camp at [[Fanjeaux]], he was faced with the desertion of local lords who had sworn fealty to him out of necessity—and attempts to enlarge his newfound domain during the summer. His forces were then greatly augmented by reinforcements from northern France, Germany, and elsewhere.{{citation needed|date=June 2021}}

De Montfort's summer campaigns recaptured losses sustained in winter months, in addition to attempts to widen the crusade's sphere of operation. Notably he was active in the [[Aveyron]] at [[Saint-Antonin-Noble-Val|St. Antonin]] and on the banks of the [[Rhône]] at [[Beaucaire, Gard|Beaucaire]]. Simon de Monfort's greatest triumph was the victory against superior numbers at the [[Battle of Muret]] in 1213—a battle in which de Montfort's much smaller force, composed entirely of cavalry, decisively defeated the much-larger, by some estimates 5–10 times larger<ref>{{harvnb|Oman|2012|pp=530–534}}</ref><ref>{{harvnb|Sumption|2011|p= 245}}</ref> and combined-force allied armies of Raymond of Toulouse, his Occitan allies, and [[Peter II of Aragon]].<ref>{{harvnb|Oman|2012|p=529}}</ref> The battle saw the death of Peter II,<ref>{{harvnb|Belloc|1938|p=94}}</ref> which effectively ended the ambitions and influence of the house of Aragon/Barcelona in the Languedoc.<ref>{{harvnb|Rogers|2010|p=37}}</ref>

In 1214, Philip II's [[Battle of Bouvines|victory at Bouvines near Lille]] ended the [[Anglo-French War (1213-1214)|Anglo-French War of 1213–1214]], dealt a death blow to the [[Angevin Empire]], and freed Philip II to concentrate more of his attentions to the Albigensian Crusade underway in the south of France.<ref>{{harvnb|Belloc|1938|p=93}}</ref> In addition, the victory at Bouvines was against an Anglo-German force that was attempting to undermine the power of the French crown. An Anglo-German victory would have been a serious setback to the crusade.<ref>{{harvnb|Tyerman|2006|p=595}}</ref> Full French royal intervention in support of the crusade occurred in early 1226, when [[Louis VIII of France]] led a substantial force into southeastern France.<ref>{{harvnb|Tyerman|2006|p=missing}}</ref>