Paganism consists of all of the old, polytheistic religions of the world.
Such religions are usually amoral or only weakly moralistic, and are centered around honoring their gods in some way.

Most of the pagan religions were forcibly replaced by the pseudoreligious dominance schemes called Christianity and Islam,
and also replaced by Zoroastrianism, and probably also by Buddhism, Manichaeism, Taoism, and/or Confucianism.

The bulk of the focus of modern paganism is upon the indo-european pagan religions of europe that were forcibly replaced by Christianity.
The only major exception to that is egyptian paganism, which is also called Kemetism.
Egyptian paganism is an afro-asiatic religion, based outside of europe, which was forcibly replaced by both Christianity and Islam.