Outer Manchuria

Outer Manchuria (Chinese: 外满洲 or 外东北; Russian: Приаму́рье or Priamurye) is an unofficial term for a territory in Northeast Asia that was formerly controlled by the Qing dynasty and now belongs to Russia. It is considered part of Manchuria by some definitions. Russia officially received this territory by way of the Treaty of Aigun in 1858 and the Treaty of Peking in 1860. The northern part of the area was also in dispute between 1643 and 1689.

Outer Manchuria comprises the present-day Russian areas of Primorsky Krai, southern Khabarovsk Krai, the Jewish Autonomous Oblast, and Amur Oblast. A Chinese claim adds the island of Sakhalin. Currently, the People's Republic of China has no claim to the territory.

The Treaty of Nerchinsk, in 1689, defined the China–Russia border as the Stanovoy Mountains and the Argun River, making Outer Manchuria a part of Qing dynasty China. After losing the Opium Wars, the Qing dynasty was forced to sign a series of treaties that gave away land and ports to the European powers; these were known as the Unequal Treaties. Starting with the Treaty of Aigun in 1858 and the Treaty of Peking in 1860, the Sino–Russian border was realigned in Russia's favor along the Amur and Ussuri rivers. As a result, China lost Outer Manchuria, as well as access to the Sea of Japan.