The Role of Atrak Border River in the Relations between Iran and Russia (1356 A.H. 1299 A.H./1261 A.H.)

Atrak River is one of the longest border rivers of Iran, whose source is the heights near Qochan in the north of Khorasan and it travels a path from east to west on the common border of Iran and Russia and recently Turkmenistan. This river has an important place in the political history of the region, a part of it in the Chat area, according to the Akhal Treaty in 1299 AH, became the official and common border of Qajar Iran and the Tsarist Russian Empire and after a few decades after the October Revolution in 1917, it was determined as the border between Iran and the Soviet Union and it was decided that at least 50% of the water of this river will enter the regions of that country. In addition to its border importance, Atrak River has always been of interest in terms of irrigation of agricultural lands and various construction facilities and creation of sources of income. Therefore, giving importance to issues related to water and border rivers such as Atrak in studies of contemporary history plays an important role in determining the behavior of water diplomacy and economic decisions. The present research, using descriptive-analytical method and relying on library and documentary sources, aims to answer the question, what effect did the Atrak River have on the hydropolitical relations of Iran and its neighbors in the direction of stability and reduction of water and border tensions? And what effect did it have on the historical developments of the east of the Caspian Sea, in terms of population and economy? The claim of the research is that due to the changes in the Atrak River bed due to natural causes and human intervention, there have always been problems and tensions in determining the borders of Iran with neighboring lands. Also, the Turkmen-inhabited region on both sides of the river has a desert climate, and the Etrak river basin is one of the water sources of this land, Therefore, the arbitrary withdrawal of water by the countries has caused challenges between the two countries, and to solve this problem, agreements were always signed in different periods, the results of which were the relative interactions of the parties in the last century