The area of present-day Azerbaijan was settled beginning in about the 8th century BC by the Medes, an ancient Aryan tribe. It became part of the Persian Empire in the 6th century BC, and the ancient religion of Zoroastrianism was introduced. From the 4th century BC until the 9th century AD, what is now the republic of Azerbaijan was regarded as the state of Caucasian Albania (Aghvan).
All this changed in 643 AD with the spreading of the Arab caliphate into Azerbaijan, bring Islam ...