Pope Leo I, also known as Saint Leo the Great, was the head of Catholic Church for 21 years (from 440 A.D. to 461 A.D.) and was born in the year 400. He was an Italian aristocrat and was the very first Pope to be called “the Great”. A native of Tuscany, he became a deacon by 431 and occupied a sufficiently important position for Cyril of Alexandria, the Patriarch of Alexandria from 412 to 444. He was chosen by the emperor to settle a dispute between Aetius and Caecina Decius Aginatius Albinus, the two highest officials in Gaul (large region of Western Europe). During his absence, Pope Sixtus III died and after his great success with the Gaul dispute, the people elected him as the new Pope.
Pope Leo was a significant contributor to the reaffirming of the papal authority and to spiritual authority in the church. He sought to erase heretics and settle all disputes. Leo expanded papal authority to different regions that the Church had some influence over such as, Campania, Tuscany and Picenum. At the Second Council of Ephesus in 449, Leo’s representatives delivered his famous Latin text called Tome. It was given as a statement of faith from Leo to the Archbishop Flavian of Constantinople dicussing the formulas of Western Christology. But the council ignored Leo’s legates and deposed Flavian and this action led to their replacement by the Council of Chalcedon. The new council was aimed at ecumenism which refers to the initiatives of the council to be aimed at increasing Christian unity or cooperation. With the death Theodosius II in 450, Anatolius, the new patriarch of Constantinople, took Leo’s Tome and spread it across the region, making it the necessary reading of religious people.
Pope Leo’s most famous political encounter was with Attila the Hun in 452. Attila had invade italy and already sacked numerous cities such as Aquileia and was headed for Rome. He sent his demands and one of them was the sister of Emperor Valentinian III be sent to him with a dowry. Instead the Emperor sent three envoys: Gennadius Avienus, one of the consuls of 450, Pope Leo the Great, and Memmius Aemilius Trygetius, the former urban prefect. The specifics of the negotiations are unknown but they reasoned well enough to cause Attila’s withdrawal from the region. He is celebrated for his heroism in the negotiations because it would have surely meant the end had Attila invaded.
The significance of Leo’s pontificate lies in his letters and sermons which created a doctrine, the Petrine Supremacy. This doctrine asserted the universal jurisdiction of the Roman bishop. Pope Leo passed away in 461 A.D. and was buried in his own monument. The Roman Catholic Church marks November 10th as the feast day of Saint Leo while the Eastern Catholic Churches celebrate him on February 18th.