<human>:  When did the Sino-Soviet split happen?
<bot>: The Sino-Soviet split happened in the late 1940s. It was a major political division between the Soviet Union and China. It began after the Second World War, when the Soviet Union supported Mao Zedong’s communist forces in the Chinese Civil War. However, Mao soon began to criticize the Soviet Union for its support of capitalism and the United States. In response, the Soviet Union withdrew its support for the Chinese communists, and the two countries became bitter enemies.