Russia. The only Caucasian territories remaining in Iranian hands were what is now Armenia, the Nakhichevan Khanate, and the Talysh Khanate. The next war, the Russo-Persian War (1826-1828), resulted in an even more humiliating defeat, with Iran being forced to cede the remaining Caucasian regions, as well as having Russian troops temporarily occupying Tabriz and Iranian Azerbaijan. As Iran was unwilling to allow the Russians to gain possession over its Caucasian territories in the North Caucasus and South Caucasus, the millennia-old ancient ties between Iran and the Caucasus region were only severed by the superior Russian force of Russia through these 19th-century wars. The area to the North of the river Aras, which included the territory of the contemporary republic of Azerbaijan, eastern Georgia, Dagestan, and Armenia, were Iranian territory until they were occupied by Russia during the 19th century. Through the course of the 19th century Iran lost to Russia regions which had been part Iran for centuries. By the end of the 19th century, the border between Iran and Russia was set more southwards, at the Aras River, which is currently the border between Iran and Armenia – Azerbaijan. Subsequently, the Russians were very influential in Northern Iran including Azerbaijan (as Northern Iran fell into Russia's sphere of influence for decades). After 1905, the representatives of Azerbaijan were very active in the Iranian Constitutional Revolution as a result to this Russian influence. Contemporary age The Russian (Tsarist) army occupied Iranian Azerbaijan in 1909 and again in 1912–1914 and 1915–1918, followed by Ottoman forces in 1914–1915 and 1918–1919; Bolshevik forces occupied Iranian Azerbaijan and other parts of Iran in 1920–1921, and Soviet forces occupied Iranian Azerbaijan in 1941, creating a very short-lived autonomous, Soviet-supported state from November 1945 to November 1946, which was dissolved after the reunification of Iranian Azerbaijan with Iran in November of the same year. The period roughly from the last major Russo-Persian War up to this date is so-called the period of high Russian influences in Iran. All of Northern Iran, including Iranian Azerbaijan, Gilan, Mazandaran, Qazvin, and many other places all the way up to Isfahan fell into the Russian sphere of influence. Russian armies were stationed in many regions of Iranian Azerbaijan, Russian schools were founded, and many Russians settled in the region, but less than in Gilan and Mazandaran. Also, Azerbaijan saw the large influx of the so-called White émigrées who fled