Zoroastrianism is a religion which has been practiced in the West Asian country of Armenia since the fifth century BC. It first reached the country during the Achaemenid and Parthian periods, when it spread to the Armenian Highlands. Prior to the Christianization of Armenia, it was a predominantly Zoroastrian land. The yazatas (deities) Mithra (Mihr) and Verethragna (Vahagn) particularly enjoyed a high degree of reverence in the country.

Gregory the Illuminator was the founder and first official head of the Armenian Apostolic Church. He converted Armenia from Zoroastrianism to Christianity in the early fourth century, making Armenia the first state to adopt Christianity as its official religion. He is venerated as a saint in the Armenian Apostolic Church and in some other churches.