The dominance of the nomads ended in the 16th century, as firearms allowed settled peoples to gain control of the region. Russia, China, and other powers expanded into the region and had captured the bulk of Central Asia by the end of the 19th century. After the Russian Revolution, the western Central Asian regions were incorporated into the Soviet Union. The eastern part of Central Asia, known as East Turkestan or Xinjiang, was incorporated into the People's Republic of China. Mongolia remained independent but became a Soviet satellite state. Afghanistan remained relatively independent of major influence by the USSR until the Saur Revolution of 1978.