The Indo-Aryans brought with them their language and religion. The Indo-Aryan and Vedic beliefs and practices of the pre-classical era were closely related to the hypothesised Proto-Indo-European religion, and the Indo-Iranian religion. According to Anthony, the Old Indic religion probably emerged among Indo-European immigrants in the contact zone between the Zeravshan River (present-day Uzbekistan) and (present-day) Iran. It was "a syncretic mixture of old Central Asian and new Indo-European elements", which borrowed "distinctive religious beliefs and practices" from the Bactria–Margiana Culture. At least 383 non-Indo-European words were borrowed from this culture, including the god Indra and the ritual drink Soma. According to Anthony,