Historically, eastern varieties of Aramaic have been more dominant, mainly due to their political acceptance in the Neo-Assyrian and Achaemenid Persian empires. With the later loss of political platforms to Greek and Persian, Aramaic continued to be used by the population. In the region of Babylonia, rabbinical schools flourished, producing the Aramaic Targums and Talmud, making the language a standard of religious scholarship. In northern Mesopotamia, the local variety of eastern Aramaic, known as Syriac, became a standard language among Christians, used in the Peshitta and by the poet Ephrem, and in the schools of Edessa and Nisibis, and by the Saint Thomas Christians in India. Among the Mandaean community of Khuzestan, another variety of eastern Aramaic, known as Mandaic, became the liturgical language of the religion. These varieties have widely influenced the less prominent western varieties of Aramaic, and the three literary, classical languages outlined above have also influenced numerous vernacular varieties of eastern Aramaic, some of which are spoken to this day (see Neo-Aramaic languages). Since the Arab conquest, most of the population of the area has undergone a language shift to Arabic.