In past times, Dari speakers have experienced political pressures to yield up their language as well. The period since the seventh-century Muslim conquest of Persia has been a time of great persecution for the Zoroastrians of Iran. Political pressures have directly resulted in language loss when Zoroastrians have deliberately abandoned their language as a means of hiding their identity so as to escape persecution. Political pressures have also led to language loss indirectly; the oppression the Zoroastrians have been experienced under Iran’s various rulers over the past thousand or so years has driven a steady stream of Zoroastrians to more tolerant areas, mostly the capital, Tehran, or abroad. Again, a complete language environment does not exist in these places, inhibiting the transmission of Dari to new generations.