This chapter seeks to explore the second-and third-century history of Christian thought in the two major centers of the western Mediterranean: Rome and Carthage. The types of Christianity that were evident in these cities differed from each other, shaped by particular circumstances and events. Furthermore, it must be kept in mind that the thinking expressed in the writings of the outstanding individuals to be surveyed in this chapter, while it was forged in these cities, did not express necessarily the thinking of the whole Christian community in that city, but often only the individual attitude of the writer concerned. In the sections of this chapter I shall consider two authors from each city  – Tertullian and Cyprian from Carthage and Hippolytus and Novatian from Rome – to outline their thinking about God, human nature, the church, and Christian living.