Ganelon

In the Matter of France, Ganelon (US: /ˌɡænəˈloʊn/, French: [ɡan(ə)lɔ̃]) is the knight who betrayed Charlemagne's army to the Saracens, 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.