Pope military aid from Pope Urban II in the ongoing Byzantine–Seljuq wars. Urban, at the council of Clermont, called the First Crusade to assist the Byzantine Empire to regain the old Christian territories, especially Jerusalem. With the East–West Schism, the Eastern Orthodox Church and the Catholic Church split definitively in 1054. This fracture was caused more by political events than by slight divergences of creed. Popes had galled the Byzantine emperors by siding with the king of the Franks, crowning a rival Roman emperor, appropriating the Exarchate of Ravenna, and driving into Greek Italy. In the Middle Ages, popes struggled with
Simon II of Clermont less independently, e.g. Château de Clermont in Loire-Atlantique, Isère and Haute-Savoie, and some that have been destroyed. See also List of châteaux in Picardy. " This article incorporates information from the French Wikipedia." " This article incorporates information from the Dutch Wikipedia." Simon II of Clermont Simon II of Clermont-Nesle (c. 1210 – 1285/86) was Seigneur (Lord) of Ailly, Maulette and Nesle (in Picardy) . Note that there is a great confusion of names and titles within this family and with people with the same or similar names, as with many other medieval lords because of contradictory and incomplete documents.