Counting gods is harder than it looks, even for experts
Polytheism simply means worshipping more than one deity, but deciding which faiths qualify is surprisingly slippery. Many Hindus call their beliefs monotheistic, Irish Christians honour a saint who began as a Celtic goddess, and some modern pagans think Zeus, Odin and Indra are one god wearing three cultural costumes.
The word itself was a polemical invention. Philo of Alexandria, a Jewish writer, coined it from Greek roots meaning many and god so he could argue against Greek religion. It faded, then came back in the 16th century through Jean Bodin and again in 1614 through Samuel Purchas. Oxford Reference warns that gods resist counting: what looks like a crowd of deities may really be several faces of a single divinity.
Worship is rarely spread evenly. Henotheism, monolatry and kathenotheism describe acknowledging many gods while devoting oneself to one, or to a select few, depending on time and setting. Hinduism shows how blurry the lines get. Vedanta, its dominant school, treats Brahman as the one ultimate reality while allowing devotees to approach it through countless deities, and Bhakti worshippers see one supreme being known by many titles.
Modern practitioners split into soft and hard camps. Soft polytheists treat gods as archetypes, forces of nature, or a single deity viewed through different cultures, an idea called omnitheism. Hard polytheists insist each god is a real, separate being and often deny that gods outside their own pantheon exist at all. Surviving traditions include Taoism, Shinto, Chinese folk religion, Santería, most traditional African religions and neopagan movements such as Wicca.
History shows pantheons swelling as states grew. City patrons were gathered together as empires spread, and conquest could subordinate one set of gods to another, as the Greek Titanomachia may reflect. Trade and contact let one deity travel: Osiris, an Egyptian god, later found worshippers in Greece. Myth and cult also diverged, since gods who fought each other in stories were often honoured side by side in temples. Epicurus went further, picturing blissful material gods living between worlds and paying mortals no attention whatsoever.
Source: Polytheism