(̓Ατροπατήνη), Byzantine Greek Adravigánon (᾿Αδραβιγάνων), Armenian Atrpatakan (Ատրպատական), Syriac Adhorbāyghān." The name Atropat in Middle Persian was transformed to Adharbad and is connected with Zoroastrianism. A famous Zoroastrian priest by the name Adarbad Mahraspandan is well known for his counsels. Azerbaijan, due to its numerous fire-temples has also been quoted in a variety of historic sources as being the birthplace of the prophet Zoroaster although modern scholars have not yet reached an agreement on the location of his birth. In the early the 19th century, Qajar Iran was forced to cede to Imperial Russia its Caucasian territories north of the Aras River (modern-day Dagestan, Georgia, Armenia, and the Republic of Azerbaijan), through the treaties of Gulistan (1813) and Turkmenchay (1828). Following the disintegration of the Russian Empire in 1917, as well as the short-lived Transcaucasian Democratic Federative Republic, in 1918, the leading Musavat government adopted the name "Azerbaijan" for the newly established Azerbaijan Democratic Republic, which was proclaimed on May 27, 1918, for political reasons, even though the name of "Azerbaijan" had always been used to refer to the adjacent region of contemporary northwestern Iran. Thus, until 1918, when the Musavat regime decided to name the newly independent state Azerbaijan, this designation had been used exclusively to identify the Iranian province of Azerbaijan. History Pre-Islamic period The oldest kingdom known in Iranian Azerbaijan is that of the Mannea who ruled a region south-east of Lake Urmia centered around modern Saqqez. The Manneans were a confederation of Iranian and non-Iranian groups. According to Professor Zadok: The Mannaeans were conquered and absorbed by an Iranian people called Matieni, and the country was called Matiene, with Lake Urmia called Lake Matianus. Matiene was later conquered by the Medes and became a satrapy of the Median empire and then a sub-satrapy of the Median satrapy of the Persian Empire. According to Encyclopædia Britannica, the Medes were an: After Alexander the Great conquered Persia, he appointed (328 BC) as governor the Persian general Atropates, who eventually established an independent dynasty. The region, which came to be known as Atropatene or Media Atropatene (after Atropates), was much disputed. In the 2nd century BC, it was liberated from Seleucid domination by Mithradates I of Arsacid dynasty, and was later made a province of the Sassanid Empire of Ardashir I. Under the Sassanids, Azerbaijan was ruled by a marzubān, and, towards the end of the period, belonged to