Ganelon

In the Matter of France, Ganelon is the knight who betrayed Charlemagne's army to the Muslims, leading to the Battle of Roncevaux Pass. His name is said to derive from the Italian word inganno, meaning fraud or deception. He is based upon the historical Wenilo, the archbishop of Sens who betrayed King Charles the Bald in 858.

Ganelon's most famous appearance is in The Song of Roland, where he is a well-respected Frankish baron, Roland's own stepfather and Charlemagne's brother-in-law. According to this chanson de geste Ganelon was married to Charlemagne's sister and had a son with her. He resents his stepson's boastfulness and great popularity among the Franks and success on the battlefield. When Roland nominates him for a highly dangerous mission (possibly even suicidally dangerous) as messenger to the Saracens, Ganelon is so deeply offended that he vows vengeance.

This vengeance becomes treachery as Ganelon plots with the pagan Blancandrin the ambush at Roncesvals. At the end, justice is served when Ganelon's comrade Pinabel is defeated in a trial by combat, showing that Ganelon is a traitor in the eyes of God. Thus Ganelon is torn limb from limb by four fiery horses.

In Canto XXXII of the Book of Inferno in Dante's The Divine Comedy, Ganelon (Ganellone) has been banished to Cocytus in the depths of hell as punishment for his betrayal.

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