St. Leo I, also known as Pope Leo the Great, was a prominent figure in Christian history. As an influential theologian and pope, St. Leo I played a significant role in shaping the development of Christianity. He is often associated with his writings on Christology, which focused on the nature of Christ and his role in salvation. Synonyms for St. Leo I include Pope Leo I, Leo the Great, and Leo Magnus. Each of these names refers to the same historical figure and is commonly used in literature and discussions related to Christian history and theology.