Fleeing persecutions, a large group of zoroastrians settled in India in the 900's. They are called the "Parsis", meaning those who come from Persia, from Iran.
The legend says that the Indian king Jadi Rana first refused their settlement, arguing that his country was already densely populated. To explain his refusal he sent the parsis a jar full of milk. The zoroastrians replied by adding sugar to the milk, sugar that dissolves itself while bettering the taste. They pledged to become a discrete and useful community, which convinced the king.
The integration of zoroastrians in India was fairly easy, as they adopted the local language and some customs while keeping their faith and their way of thinking, without proselyting.
Parsis have been among the founders of the city of Mumbai, where most of them live today. The giant firm Tata, a pioneer in auto and telecommunication industries, is the zoroastrians' main contribution to India's economy.