In the third century B.C.E., the lake marked the rough border between the tribes of the
Xiongnu Confederation and the
Yuezhi. Later, in the early 2nd century, the Xiongnu successfully seized much of the area from the Yuezhi. During the Han-Xiongnu wars, Lake Zaysan and the Black Irtysh were a point of contention between the Chinese Han Dynasty and the Xiongnu, with a notable campaign made in the region by general
Huo Qubing. From the early 4th century, Lake Zaysan and the Irtysh on either side of it came under the control of three successive Turkic empires: the
Rouran Khaganate, the
First Turkic Khaganate, and the
Second Turkic Khaganate. After the reformation of the nomadic state by the Gokturks in the 500s and their subsequent division into eastern and western halves, Lake Zaysan was conquered by China's Tang Dynasty in the 600s during the Battle of Irtysh River. After the loss of the Tang's northern possessions, the lake came to be governed by various nomadic tribes of the Karluks and the Oirats during the middle medieval period from the 700s–1000s. Two major powers controlling the region from the 1000s–1215 were the Kara-Khanids and the Qara-Khitai, the latter being overrun by the Mongol general Jebe in 1216. From thence, Lake Zaysan passed into Mongol possession. When the empire was yet unified, the lake served as a waypoint for large Mongol expeditions into Central and Western Asia from Mongolia, such as those of
Genghis Khan (1224) and
Hulagu Khan (1251). The region continued to be administered under the Yuan Dynasty, before later being divided between local nomadic powers. Timur launched a military expedition to the lake and the Black Irtysh in 1391 in pursuit of the Moghul khan Qumaruddin Dughlat. The first Russian to reach the area was Ivan Bukholts who ascended the Irtysh to build a fort and search for gold. In 1715 he was driven back downriver by the
Oirats, who had established the
Zunghar Khanate in the region. The Chinese
Qing Empire conquered the Zunghar state in the 1750s. This prompted an increase in the Russian authorities' attention to their borderland; in 1756, the
Orenburg Governor
Ivan Neplyuyev even proposed the annexation of the Lake Zaysan region, but this project was forestalled by Chinese successes. Concerns were raised in Russia (1759) about the (theoretical) possibility of a Chinese fleet sailing from Lake Zaysan down the Irtysh and into Western Siberia. A Russian expedition visited Lake Zaysan in 1764, and concluded that such a riverine invasion would not be likely. Nonetheless, a chain of Russian pickets was established on the
Bukhtarma River, north of Lake Zaysan. Thus the border between the two empires in the Irtysh basin became roughly delineated, with a (sparse) chain of guard posts on both sides. The situation on the Zaysan in the mid-19th century is described in a report by A. Abramof (1865). Even though the Zaysan region was recognized by both parties as part of the Qing Empire, it had been annually used by fishing expeditions sent by the
Siberian Cossack Host. These summer expeditions started in 1803. And in 1822–25, their range was expanded through the entire Lake Zaysan and to the mouth of the Black Irtysh. Through the mid-19th century, the Qing presence on the upper Irtysh was mostly limited to the annual visit of the Qing
amban from
Chuguchak to one of the Cossacks' fishing stations (
Batavski Piket). The border between the Russian and the Qing empires in the Irtysh basin was established along the line fairly similar to China's modern border with Russia and Kazakhstan by the
Convention of Peking of 1860. The actual border line pursuant to the convention was drawn by the Protocol of
Chuguchak (1864), leaving Lake Zaysan on the Russian side. The Qing Empire's military presence in the Irtysh basin crumbled during the
Dungan revolt (1862–77). After the fall of the rebellion and the reconquest of Xinjiang by
Zuo Zongtang, the border between the Russian and the Qing empires in the Irtysh basin was further slightly readjusted, in Russia's favor, by the
Treaty of Saint Petersburg (1881). ==See also==