China–Russia border

What's left of a much longer border

In 1978 the US State Department described the China–Soviet boundary as 4,150 miles long, split into two nearly equal parts by Mongolia.^[1] The western part ran about 1,850 miles through the mountains of Central Asia. East of Mongolia, 2,300 miles followed mostly the Argun, Amur and Ussuri rivers.^[1]

Almost all of the western part is now China's border with Kazakhstan, Kyrgyzstan and Tajikistan. Russia keeps only a short stretch in the Altai Mountains, where the old Turkestan sector ended next to Mongolia.^[1] So today's China–Russia border is mainly the old Manchurian–Siberian sector. It runs from the Mongolian tripoint to the Tumen River, where it meets North Korea about 10 miles above the river's mouth.^[1]

Nerchinsk: the first line

Russia crossed Siberia fast. Perm, west of the Urals, marked its eastern limit in 1580, and Russians reached Okhotsk on the Pacific in 1638.^[1] Following the Lena to its source, Russian explorers reached the Amur valley and ran into peoples under the Manchu (Qing) Empire. After several battles the Manchus forced the Russians out of the middle and lower Amur.^[1]

The 1689 Treaty of Nerchinsk created the first boundary between the two empires. It followed the Argun, then ran along the Yablonovyy and Stanovoy mountains to the Pacific, well north of the Amur.^[1] In 1727 the Bur and Kiakhta treaties extended the line west, north of Mongolia. That line lasted, with small changes, until 1858.^[1]

Aigun and Peking: the Amur and the Ussuri

By the 19th century the Manchu dynasty was weaker and under pressure from foreign powers.^[1] The Treaty of Aigun in 1858 moved the boundary south to the Amur. Russia gained an estimated 598,000 square km. Manchu settlers in the “64 villages” on the north bank were allowed to stay under Manchu rule, and the land between the Ussuri and the Pacific was to be ruled in common.^[1]

The Treaty of Peking in 1860 settled the land Aigun had left in doubt. The boundary would follow the Ussuri, cross Lake Khanka and run south to the Tumen. That gave Russia another 400,000 square km, including the harbour of Vladivostok.^[1] Together, the two treaties created the basic border that still divides China's northeast from the Russian Far East.^[1]

Beijing later called these “unequal” treaties that a weak China was forced to sign.^[4] During the Boxer Rebellion in 1900, Russia expelled the Manchu inhabitants of the 64 villages and took control of that land.^[1]

Whose islands?

The treaties described the land on each bank but never said exactly where in the river the line ran. The US Geographer noted in 1978 that the boundary in the Argun, Amur and Ussuri had “never been precisely delimited”.^[1] A 1951 agreement let ships use the main channel whatever side of the line it was on.^[1] Moscow argued that the 1860 treaty put the line along the Chinese bank.^[4] Near Khabarovsk, China said the border followed the main Amur channel, while the Soviet Union used a smaller channel to the south and held the islands between them.^[1]

Talks in 1964 made some progress. Soviet negotiators accepted the thalweg (the deepest channel) as the river boundary, which would have given 400 river islands, including Zhenbao, to China. But Moscow would not sign until the Khabarovsk islands were settled, and the talks broke down that July.^[4]

On 2 March 1969, according to CNA's study, Chinese troops ambushed Soviet border guards on Zhenbao Island (Damansky in Russian), a small, uninhabited island in the Ussuri. Thirty-one Soviet border guards died, and Chinese losses are still unknown.^[4] On 15 March the two sides fought there again with larger forces. Each blamed the other, though most scholarship points to the Soviet side. More clashes followed along the border.^[4] The Soviet Union hinted several times that it might use nuclear weapons. By September China had agreed to talk, and premiers Alexei Kosygin and Zhou Enlai met at Beijing airport on 11 September.^[4]

Settled at last

Russia and China signed border agreements in 1991 and 1994 for the eastern and western sections, but a small part of the east stayed open.^[2] In October 2004, on a visit to China, President Vladimir Putin and President Hu Jintao signed the final agreement on the eastern sector. It split about 375 square km: Bolshoi Island on the Argun, plus Tarabarov and Bolshoi Ussuriysky islands where the Amur meets the Ussuri near Khabarovsk. Russia's State Duma ratified it in May 2005.^[2]

On 14 October 2008, Russia handed over about 170 square km: Tarabarov Island (Yinlong in Chinese) and half of Bolshoi Ussuriysky (Heixiazi).^[3] Russia's foreign ministry said the handover completed the legal establishment of the whole border.^[3]

“This event completes the delineation and the legal establishment of all parts of the Russian-Chinese border.”^[3]