Augustine of Hippo (354-430) was the son of a Christian mother and a pagan father. He spent the early years of his life shunning the simplicity of Christianity and seeking inner peace through philosophical knowledge. He was deeply disturbed by his carnal passions, though he kept a mistress who bore him a son, Adeodatus.
Augustine moved to Rome in 383 and became a teacher of rhetoric in Milan in 384. Listening to the sermons of Bishop Ambrose of Milan, who was in the habit of explaining the Old Testament symbolically, Augustine found it possible to accept God.
Augustine's Confessions describes his eventual conversion to Christianity in vivid detail. His writings made him one of the most important philosophers and theologians of the early Church. He dealt with many subjects, such as proof of the existence of God and original sin, but he also took a view on ethical and social issues.
Read more of St. Augustine's writings at New Advent's The Fathers of the Church.
Augustine was one of the most prolific Latin authors in terms of surviving works, and the list of his works consists of more than one hundred separate titles. Read more at Wikipedia.