Proto-Indo-Iranian

Proto-Indo-Iranian, is the  reconstructed proto-language of the Indo-Iranian branch of  Indo-European. Its speakers, the hypothetical Proto-Indo-Iranians, are assumed to have lived in the late 3rd millennium BC, and are usually connected with the early Andronovo archaeological horizon. Proto-Indo-Iranian was a Satem language, likely removed less than a millennium from the late Proto-Indo-European language, and in turn removed less than a millennium from the Vedic Sanskrit of the Rigveda. It is the ancestor of the Indo-Aryan languages, the Iranian languages, the Dardic languages and the Nuristani languages. The main phonological change separating Proto-Indo-Iranian from Proto-Indo-European is the collapse of the ablauting vowels *e, *o, *a into a single vowel, Proto-Indo-Iranian *a (but see Brugmann's law). Grassmann's law, Bartholomae's law, and the Ruki sound law were also complete in Proto-Indo-Iranian.
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