Sino-Soviet Treaty of Friendship and Alliance

The Treaty of Friendship and Alliance (Chinese: 中蘇友好同盟條約, Russian: Договор о дружбе и союзе между СССР и Китайской Республикой) was a treaty signed by the National Government of the Republic of China and the Government of the Union of Soviet Socialist Republics on 14 August 1945, at the time of Japan's surrender. Soviet and Mongolian troops then occupied Inner Mongolia and Manchuria, after they had seized it from the Japanese during World War II. During the preceding Sino-Soviet negotiations, despite the lack of a consensus on a formal treaty, the Soviets had already launched Soviet invasion of Manchuria on August 9 1945 and, one week later, seized the Allies-recognized Chinese territory of Manchuria and Inner Mongolia (then known as Manchukuo and Mengjiang) from the Japanese Empire.

Source: Wikipedia — Sino-Soviet Treaty of Friendship and Alliance (CC BY-SA 4.0)