With the arrival of Islam in Iran simultaneously with its expansion, Zoroastrians faced social, political and cultural deprivation. Consequently some of them converted to Islam and only a minor group remained faithful to their faith. Though their number decreased in Iran until the start of the Qajar period, by the end of this era, they had a significant role in commerce. The foundation of firms, like: Jamshidian, Jahanian, Yeganegi, indicates their commercial power. These firms were involved in affairs such as: exchange, banking and landing. Zoroastrians were perceived as honest and truthful people, resulting in the government trusting them. With the succession of the Constitutional Movement in Iran, Zoroastrians as one of the religious minorities elected Arbab Jamshid, a commercially powerful man, as their parliamentary representative. Thus after a period of several centuries Zoroastrian community came out of an isolation. But the success of these firms did not last long, and finally with interference from foreign citizens like that of the Russians, the firms eventually turned bankrupt.