Abstract
The article examines the historical and geographical appearance of the Irtysh River in the Middle Ages and modern times. The Irtysh River is one of the most important rivers in Eurasia. This river had a special role both in the Middle Ages and in modern times. It is unique even now. The river originates in China, most of it passes through Kazakhstan and flows into the Ob River in Russia. The Ob, in turn, flows into the Arctic Ocean. The Irtysh River is often mentioned in Arab-Persian sources in connection with various military-political and economic conditions in the Eurasian space. In addition, the sources provide information about the flora and fauna of the river, its natural resources and widespread economic use. The scientific heritage of Academician V.V. Bartold contains important and interesting information about the Irtysh River, which played an important role in the economy and history of the countries of Central Asia, and the entire continent of Eurasia. The scientific heritage of Academician V.V. Bartold, based on Arab-Persian sources, shows that the Irtysh River occupied an important place in the Eurasian space. In this regard, this article makes an attempt to collect and summarize this information, thereby forming the historical and geographical appearance of the Irtysh River.