‘Paganism’ was first invented towards the end of its existence, during the period covered by this volume. Previously there had been ‘religion’, or ‘piety’, evoked by the many gods of many peoples. The monotheistic religions – Judaism, and its recent offspring Christianity – were aberrations. But as Christianity's fortunes improved, it felt the need to define, as diminishingly as possible, ‘the other’. Hence – in the Latin-speaking world and, with any frequency, only from the mid-fourth century onward – ‘paganism’, from paganus, meaning originally either a rustic or a civilian (non-soldier), in other words ‘not one of ours’. In the Greek-speaking world, adherents of the old religion came in the fourth century to be referred to as ‘Hellenes’, a different sort of limitation, but still a limitation, which had however the virtue of drawing attention to Greek culture's role as a common frame of reference for the various local polytheisms of the eastern Mediterranean. The convenience of ‘paganism’, in particular, was that, as a single cultural hypostasis, undifferentiated either spatially or chronologically, it could in toto be credited with whatever infamy had at any time in the past attached to alleged cultic abuses, however isolated. Because of the pejorative connotations of ‘paganism’, and in order to underline that the cult of the many gods, whether in the ancient Mediterranean world or anywhere else, does not have to be seen through Christian eyes, we shall speak of ‘polytheism’. Admittedly, ‘polytheism’ too is a clumsy and implicitly monotheist category, since it attaches a single label to a range of religions whose most obvious common denominator is apparent only from a monotheist perspective; but it is a less nakedly offensive formulation than ‘paganism’.