protoIranian

Proto-Iranian is the reconstructed ancestor of the Iranian languages, the branch of the Indo-European family that includes Avestan, Old Persian, Persian (Farsi), Dari, Kurdish, Pashto, Balochi, Ossetian, Tajik, and related tongues. It follows Proto-Indo-Iranian and precedes the diversification into Eastern and Western Iranian languages. The reconstruction rests on systematic comparison of attested Iranian languages and related Indo-Iranian branches.

Scholars place Proto-Iranian in the late Bronze Age or early Iron Age, roughly in the first millennium BCE, with a homeland in or near the Iranian plateau and the western Eurasian steppe. External evidence from archaeology is indirect; linguistics relies on regular correspondences in consonants, vowels, morphology, and lexicon across descendants and on the oldest Iranian texts: Avestan and Old Persian. Avestan preserves the oldest phases of the language family.

Linguistically, Proto-Iranian shows innovations that distinguish Iranian from other Indo-European branches, including a characteristic arrangement of consonants and a system of noun declensions and verbal morphology that in many descendants becomes simplified or restructured. The descendant languages diverged into Western Iranian (including Persian, Kurdish, Balochi, and others) and Eastern Iranian (including Avestan and Ossetian) lineages, among which Old Persian and later Persian became prominent in imperial Iran, and Avestan preserved sacred religious vocabulary.

The study of Proto-Iranian underpins understanding of the historical spread of Iranian peoples and languages across West and Central Asia and their long-standing contact with neighboring cultures.