Martin IV

Pope Martin IV (Latin: Martinus IV; born Simon de Brion; c. 1210 – 28 March 1285), was the head of the Catholic Church and leader of the Papal States from 22 February 1281 until his death on 22 March 1285. He was the last French pope to hold his court in Rome before the papacy moved to Avignon.

Before his election, Simon de Brion was a prominent French cleric who served as chancellor to Louis IX of France and was made a cardinal by Pope Urban IV in 1261. His papacy was marked by close dependence on Charles of Anjou, whom he appointed Senator of Rome, and by significant political conflicts, including the excommunication of the Byzantine Emperor Michael VIII Palaiologos, which ended the fragile union between the Eastern Orthodox and Roman Catholic Churches established at the Second Council of Lyon in 1274. Martin IV also faced the Sicilian Vespers uprising and excommunicated Peter III of Aragon, declaring a crusade against him in an unsuccessful attempt to maintain Angevin control over Sicily.