After Japan's fall 1938 victory in the Battle of Wuhan, its forces advanced deep into Communist territory and redeployed 50,000 troops to the Shanxi-Chahar-Hebei Border Region.

[3]: 122 During the Second Sino-Japanese War, the Communist Party built a broader coalition in the Shanxi-Chahar-Hebei Border Region.

[3]: 137 At the beginning of the Chinese Civil War in 1946, large Nationalist forces entered the Shanxi-Chahar-Hebei Border Region.

[3]: 149 By late 1948, the Nationalists' conventional armed forces had been ejected from the region, although Nationalist-affiliated militia remained active thereafter.

[3]: 145 When the Chinese Civil War began after the defeat of the Japanese, the Shanxi-Chahar-Hebei Field Army had more than 180,000 soldiers.