10 November is the memorial of Pope St Leo the Great.
Pope Leo I was born in Tuscany and while little is known of his early life we do know that as a deacon he strongly opposed the heresy of Pelagianism and as Pope (after 440) was rigidly orthodox in, especially, his Christology, affirming the Church's teaching that Christ was both fully human and fully divine.
Leo is only one of two Popes (and the first) in over 1000 years to be afforded the title "the Great". He is a doctor of the Church. Secularly he is known for having met Attila the Hun outside Rome in 452, and persuading him to turn back from his invasion of Western Europe. Finally, Leo is also the 9th longest reigning pope, from 440 – 461; 21 years, 1 month, and 13 days in total.