Augustine of Hippo (354-430) grew up in Roman North Africa. He studied in Carthage, then spent time in Italy teaching philosophy and rhetoric. Ultimately, he moved back to Africa to found a monastery and spent the rest of his life traveling the Punic-speaking countryside, preaching and planting churches.
Saint Augustine has an incredible legacy of laying Christian theological and Western philosophical foundations. The Roman Empire was going through several changes during and around his life. Though many religions were still popular, Christianity grew, was legalized, and became official. The center of power shifted to Constantinople. Rome was sacked. Augustine personally experimented with many sins. Fittingly, his doctrine focused on topics that included unity, righteousness, and human limitation.