A key theme which the Protestant Reformers recovered and sought to apply to Christendom was that of Christ’s Two Kingdoms. In the one Christian society under God, Christ’s dominion manifested itself in two “orders,” regnum (civil government) and sacerdotium (the visible church). But what was the proper relationship between these two? Over what areas was each ordained to rule, was either superior to the other, and in cases of conflict, which was to take priority? These questions occupied many writers from the Patristic era through the Middle Ages, and multiple positions were debated for long centuries without resolution. On the very eve of the Reformation, important questions about popes and kings remained “on the table” and animated much of the Reformation’s protest against Rome. This course aims to provide a broad overview of the Two Kingdoms question prior to the Reformation, in order to deepen understanding of Church history proper and better contextualize our advocacy and defense of Protestant political wisdom for today.