China–Kyrgyzstan border

The origins of the border date from the mid-19th century, when the Russian Empire expanded into Central Asia and was able to establish its control over the Lake Zaysan region.

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 Ili River basin was further slightly readjusted, in Russia's favour, by the Treaty of Saint Petersburg (1881) and a series of later protocols.

[4] In 1915 an agreement was signed more precisely delimiting the border the Ili Valley and Dzungarian Alatau region.

[4] The southernmost section of the frontier (i.e. roughly the southern half of the modern China-Tajikistan border) remained undemarcated, owing partly to the ongoing rivalry between Britain and Russia for dominance in Central Asia known as the Great Game; eventually the two agreed that Afghanistan would remain an independent buffer state between them, with Afghanistan's Wakhan Corridor being created in 1895.

The border agreement was finalised in 2009, with China giving up part of the Khan Tengri Peak while Kyrgyzstan ceded the Uzengi-Kush, a mountainous area located south of the Issyk Kul region.