His great treatise, in seven books, Adversus Gentes (or Nationes), on account of which he takes rank as a Christian apologist, appears to have been occasioned by a desire to answer the complaint then brought against the Christians, that the prevalent calamities and disasters were due to their impiety and had come upon men since the establishment of their religion.
Cities and kingdoms were allotted to their several patronage on a system fully expounded by Manilius: Hos erit in fines orbis pontusque notandus, Quem Deus in partes per singula dividit astra, Ac sua cuique dedit tutelae regna per orbem, Et proprias gentes atque urbes addidit altas, In quibus exercent praestantia sidera vires.s Syria was assigned to Aries, and Syrian coins frequently bear the effigy of a ram; Scythia and Arabia fell to Taurus, India to Gemini.
On the other hand, gentes and phratriae, which had no natural head, had special priests chosen from their members; for every circle of ancient society, from the family up to the state, was a religious as well as a civil unity, and had its own gods and sacred rites.
Apart from the definite evidence, the theory of a racial distinction gains probability from the fact that it explains the survival of the distinction between the patricii, men with a family and genealogy, and the rest of the citizens, for some time after the latter had acquired the legal status of patres and were organized in gentes of their own; for on this theory privilege would belong not to all who could trace free descent but only to those who could trace descent to an ancestor of the conquering race.
There had consequently grown up within the state a large artisan class, excluded from the old patrician gentes and therefore from the state cult: at the same time the beginnings of commerce had opened relations with neighbouring peoples.