Zoroastrianism, a religion which arose among Iranian peoples some 3,000 years ago, was the religion of the majority of Iranians prior to the Arab conquests of the mid-7th century. Since that time, a steady process of to Islam has left a small Zoroastrian minority of 20,000 or less in Iran today. While community leaders are making efforts to keep the religion alive, factors such as emigration, intermarriage, and low birth rates now put the very survival of this ancient faith into question, not just throughout the global diaspora but within the land of its birth. Zoroastrianism is one of the world's oldest living faiths. Tracing back most likely to sometime in the 2nd millennium BCE,1 it became the national religion of many Iranian peoples and was the state religion of the Sasanian Empire from the 3rd century CE until the Arab conquest in the 640s. During the subsequent centuries, most Iranians converted to Islam, and a small group of Zoroastrians emigrated to India where they established the Parsi (Persian) community.2 In Iran, numbers have now dwindled to less than 20,000, at least according to official figures,3 although since the Iranian Revolution of 1979 there has been much speculation about the extent of re-conversion to Zoroastrianism by Iranian Muslims disaffected by the country's present Islamic regime. The causes of the Zoroastrian community's decline in Iran date back to the Arab conquests and have been compounded by some contemporary issues. In historical terms, there have been various explanations as to why a majority of Iranians abandoned their traditional faith in favor of Islam, especially since the long-popular conversion by the sword theory has now been largely discredited. Indeed, the evidence is rather that at least during the first century or so, the Arabs were actually mostly reluctant to allow non-Arabs into their prospering community,4 requiring them to acquire an Arab sponsor [mawla] through whom they could obtain a kind of honorary Arab tribal identity.5 That so many non-Arabs chose to do so can be taken as evidence that membership in this community was very attractive, and encompassed temporal as well as spiritual advantages. Another factor often cited is the dependence of the Zoroastrian priesthood on state support, which was lost to them with the fall of the Sasanians. Later, with the increasing application of the then-nascent norms of Islamic law from the 'Abbasid period onwards, legal issues such as family inheritances accruing entirely to individuals converting to Islam, the stipulation that children of mixed marriages be raised as Muslims, and the prohibition against proselytization by non-Muslims, as well as social issues such as localized persecution of non-Muslims by members of the Muslim majority, were all factors leading numerous Iranian Zoroastrians to embrace an Islamic identity. Contrary to some common perceptions, the Islamization of Iran was not instantaneous but rather took place over several centuries. Nevertheless, in urban areas an estimated 80% of the population had become Muslim by the 10th century.6 Over the subsequent centuries the rural communities followed, although their case is more difficult to document. What is clear is that the contexts in which Zoroastrianism survived in Iran were largely rural, especially in the villages around the cities of Yazd and Kerman.7 This reality persisted well into the 20th century. By the 19th century the living conditions of Iran's Zoroastrians had deteriorated to such an extent that the Parsis, who had begun to prosper in British India, began to send financial aid and lobby Iran's government on behalf of their co-religionists. It was through such pressure that the Qajar monarch Naser al-din Shah repealed the jizya (a tax on non-Muslim subjects) on Zoroastrians in 1882. Parsis, meanwhile, built schools and medical clinics for Zoroastrians in Iran.8 The 20th century saw additional helpful trends, such as the Iranian nationalism of Pahlavi ruler Reza Shah (r. …