Zoroastrianism or Mazdaism.
Zoroastrianism
The most widely practiced religion in Ancient Persia is now known as Zoroastrianism. However, in the centuries after the Islamic conquest of Persia, most Persians converted to Islam (both by choice and from fear of violence). Islam (specifically Twelver Shiite Islam) is the dominant religion among ethnic Persians today.
Most Persians today are Muslim, but before the advent of Islam in Persia, most Persians were Zoroastrians.
Monotheistic, because the Persian religion was Zoroastrianism which is a monotheistic religion
Persians are practicing the religion of Islam.
Jeid
Most Persians today are Muslim, but before the advent of Islam in Persia, most Persians were Zoroastrians.
ancient Persians
islam
Iran
Iran.