Leo the Great (c. 400–461) was one of the most influential figures in the early Christian Church, serving as Pope from 440 until his death. Born in Tuscany or possibly Rome, he rose through the ecclesiastical ranks to become a defining voice of papal authority and Christian orthodoxy. His collection of "Letters" reveals a masterful administrator and theologian, addressing doctrinal disputes, Church governance, and the challenges of a crumbling Roman Empire. He famously persuaded Attila the Hun to turn back from Rome in 452. Leo was declared a Doctor of the Church and canonized as a saint.