Paganism is, in general terms, the belief in various deities, as distinct from the Abrahamic religions of Judaism, Christianity and Islam, all of which are monotheistic. This form of religion was widely practiced in the ancient world by almost all civilisations. With the advent and Roman adoption of Christianity, paganism came to be viewed as synonymous with barbarism and became, alongside the similar term "heathen", a generally derogatory word.
Paganism was almost stamped out from Europe to Persia by the combined efforts of Christianity and Islam. However, many pagan traditions are present and/or thrive in the rest of the world. Additionally, many European pagan traditions are being revived by neo-pagan believers.