What is the history of the azerbaijan?

During Median and Persian rule, many Albanians adopted Zoroastrianism and then switched to Christianity prior to coming of Muslim Arabs and more important Muslim Turks. The Turkic tribes are believed to have arrived as small bands of ghazis whose conquests led to the Turkification of the population as largely native Caucasian and Iranian tribes adopted the Turkic language of the Oghuz and converted to Islam over a period of several hundred years.[1]After more than 80 years of colonization under the Russian empire in the Caucasus, the Azerbaijan Democratic Republic was established in 1918. The state was invaded by Soviet forces in 1920, and remained under Soviet rule until the collapse of the USSR in 1991.