Zoroastrianism in India in the context of "Irani (India)"

Zoroastrianism, also called Mazdayasna or Behdin, is an Iranian religion centred on the Avesta and the teachings of Zarathushtra Spitama, who is more commonly referred to by the Greek translation, Zoroaster (Greek: Ζωροάστρις Zōroastris). Among the world's oldest organized faiths, its adherents exalt an uncreated, benevolent, and all-wise deity known as Ahura Mazda (𐬀𐬵𐬎𐬭𐬀⸱𐬨𐬀𐬰𐬛𐬁), who is hailed as the supreme being of the universe. Opposed to Ahura Mazda is Angra Mainyu (𐬀𐬢𐬭𐬀⸱𐬨𐬀𐬌𐬥𐬌𐬌𐬎), who is personified as a destructive spirit and the adversary of all things that are good. As such, the Zoroastrian religion combines a dualistic cosmology of good and evil with an eschatological outlook predicting the ultimate triumph of Ahura Mazda over evil. Opinions vary among scholars as to whether Zoroastrianism is monotheistic, polytheistic, henotheistic, or a combination of all three. Zoroastrianism shaped Iranian culture and history, while scholars differ on whether it significantly influenced ancient Western philosophy and the Abrahamic religions, or gradually reconciled with other religions and traditions, such as Christianity and Islam.

Originating from Zoroaster's reforms of the ancient Iranian religion, Zoroastrianism began during the Avestan period (possibly as early as the 2nd millennium BCE), but was first recorded in the mid-6th century BCE. For the following millennium, it was the official religion of successive Iranian polities, beginning with the Achaemenid Empire, which formalized and institutionalized many of its tenets and rituals, and ending with the Sasanian Empire, which revitalized the faith and standardized its teachings. In the 7th century CE, the rise of Islam and the ensuing Muslim conquest of Iran marked the beginning of the decline of Zoroastrianism. The persecution of Zoroastrians by the early Muslims in the nascent Rashidun Caliphate prompted much of the community to migrate to the Indian subcontinent, where they were granted asylum and became the progenitors of today's Parsis. Once numbering in the millions, the world's total Zoroastrian population is estimated to comprise between 110,000 and 120,000 people, with most of them residing either in India (50,000–60,000), in Iran (15,000–25,000), or in North America (22,000). The religion is thought to be declining due to restrictions on conversion, strict endogamy, and low birth rates.

As part of the early Muslim conquests, which began under Muhammad in 622, the Rashidun Caliphate conquered the Sasanian Empire between 632 and 654. This event led to the decline of Zoroastrianism, which had been the official religion of Persia (or Iran) since the time of the Achaemenid Empire, circa 550 BC. The persecution of Zoroastrians by the early Muslims during and after this conflict prompted many of them to flee eastward to India, where they were taken as refugees by various kings.

While Arabia was witnessing the rise of Islam in the 7th century, Persia was struggling with unprecedented political, economic and social issues as well as military weakness; the Sasanian army had greatly exhausted itself in the Byzantine–Sasanian War of 602–628. Following the execution of Sasanian shah Khosrow II in 628, Persia's internal political stability began to deteriorate rapidly, leading to ten new royal claimants being enthroned within the next four years. Shortly afterwards, Persia was further devastated by the Sasanian Interregnum, a large-scale civil war that began in 628 and resulted in the government's decentralization by 632.

The Avesta is the text corpus of religious literature of Zoroastrianism. All its texts are composed in the Avestan language and written in the Avestan alphabet. Modern editions of the Avesta are based on the various manuscripts that have survived in India and Iran.

The individual texts of the Avesta were originally oral compositions. They were composed over a long period of several centuries during the Avestan period (possibly ranging from 15th century BCE – 4th century BCE). The written transmission began much later during the Sasanian era (224 to 651 CE), with the creation of the Avestan alphabet. The resulting texts were then compiled into the multi-volume edition of the Sasanian Avesta. This edition was lost sometime after the 10th century CE, and only a small portion of it has survived, scattered across a number of individual manuscript traditions. The oldest surviving fragment of such a manuscript dates to 1323 CE.

The persecution of Zoroastrians is a significant aspect of the later part of the community's history. It is speculated that religious strife existed between Zoroastrians and early Christians, particularly within the context of the Roman–Persian Wars, though the extent of this phenomenon remains unclear. While it was a widespread religion in West Asia for over a millennium, Zoroastrianism began to decline drastically in the aftermath of the Muslim conquest of Persia. The annexation of the Sasanian Empire by the Rashidun Caliphate marked a monumental shift for the former's Zoroastrian-majority society, which was eventually subsumed by the ensuing process of Islamization. During this period, discrimination and harassment against Zoroastrians typically took place in the form of forced conversions and sparse violence. Early Muslims who arrived in the region are recorded to have destroyed Zoroastrian temples or repurposed them as mosques. Zoroastrian practices gradually became circumscribed under Islamic law, which included the levying of the jizya, a tax on non-Muslims.

Early Muslim behaviour with Zoroastrians may have been motivated in part by the fact that they are not explicitly classified as "People of the Book" in the Quran. Although some interpretations do extend this status to the community, the wider consensus among Muslim scholars is that "People of the Book" only identifies the followers of pre-Islamic Abrahamic religions—chiefly Judaism and Christianity—and consequently excludes Zoroastrianism, which is classified as an Iranian religion. Thus, the relative lack of amnesty and privileges for Zoroastrians at this time prompted a large part of the community to flee from Persia to neighbouring India, where they were granted asylum by local kings. The descendants of these Zoroastrian refugees of the early Muslim conquests are known as the Parsi people, who comprise the most prominent community of Indian Zoroastrians today.

In 2012, a study by the Federation of Zoroastrian Associations of North America (FEZANA) published a demographic picture of Zoroastrianism around the world, in comparison with an earlier study from 2004. It projected a global Zoroastrian population of 111,691–121,962 people, with roughly half of this figure residing in just two countries: India and Iran. These numbers indicated a notable population decline in comparison with the earlier projection of 124,953 people.

The larger part of the Zoroastrian population comprises the Parsis, a community standing at around 50,000 people in India according to the 2011 census and around 2,348 in Pakistan according to the 2023 census. In 1994, the Zoroastrian Society of Ontario estimated that there were around 100–200 Zoroastrians residing in Afghanistan.