Proto-Indo-Iranian religion

Proto-Indo-Iranian religion means the religion of the Indo-Iranian peoples prior to the earliest Hindu and Zoroastrian scriptures. These share a common inheritance of concepts including the universal force *rta (Sanskrit rta, Avestan asha), the sacred plant and drink *sauma (Sanskrit Soma, Avestan Haoma) and gods of social order such as *mitra (Sanskrit Mitra, Avestan and Old Persian Mithra, Miϑra) and *bhaga (Sanskrit Bhaga, Avestan and Old Persian Baga). Proto-Indo-Iranian religion is an archaic offshoot of Indo-European religion.

Indo-Iranian languages include three subgroups: first Indo-Aryan languages (including the Dardic languages); second Iranian languages (east and west) and third Nuristani languages. From these various and dispersed cultures, a set of common ideas may be reconstructed from which a common, unattested proto-Indo-Iranian source may be deduced.

Beliefs developed in different ways as cultures separated and evolved. For example, the cosmo-mythology of the peoples that remained on the Central Asian steppes and the Iranian plateau is to a great degree unlike that of the Indians, focused more on groups of deities (*daiva and *asura) and less on the divinities individually. Indians were less conservative than Iranians in their treatment of their divinities, so that some deities were conflated with others or, conversely, aspects of a single divinity developed into divinities in their own right. By the time of Zoroaster, Iranian culture had also been subject to the upheavals of the Iranian Heroic Age (late Iranian Bronze Age, 1800–800 BCE), an influence that the Indians were not subject to.

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