On December 22, 1937, the Japanese aggressors assembled more than 5,000 infantrymen and cavalrymen to protect their rear area and communication lines. They set out from Taigu, Yuci, Shouyang, Yangquan, Pingding and Xiyang in Shanxi Province for a six-point convergent attack on men of the Eighth Route Army active in the area southeast of Shouyang. The 772nd Regiment of the Eighth Route Army's 129th Division fought the enemy on interior lines while the 769th Regiment attacked on exterior lines, eventually forcing the Japanese troops to withdraw on December 26, with more than 700 casualties. This brought about favorable conditions for the establishment of the base areas in the Shanxi-Hebei-Henan Border Area.