According to Ademar of Chabannes, Agen was a vassal of the Count of Toulouse. Their holdings in the Saintonge are referenced in a document of 1021, which is found in the cartulary of Saint Jean d'Angély.
B. S. Bachrach, Fulk Nerra, [the Neo-Roman Consul, 987–1040: A Political Biography of the Angevin Count] (Berkeley: University of California Press, 1993), 69.
