1939年12月,傅作义军为牵制塞北日军南下,发动包头战役。傅军袭击包头后,日本驻蒙军进犯绥西,1940年1月底至2月初,日军连陷五原、临河、陕坝。日军占领五原后,在关于五原控制问题上驻蒙军司令冈部直三郎与参谋长田中新一之间发生分歧。冈部主张执行战前方面军的命令,在适当的时机从五原撤退;田中则计划依靠驻包头日军支援,通过伪蒙古军、绥西联军以及绥西警备军担当该地区的防务,由此达到将五原一带控制在日本势力下之目的。这一分歧使傅作义军利用日军主力认为达成目的后相继撤回原驻防地的机会实施反攻,并取得了五原战役的胜利。 December 1939, Fu Zuoyi army to contain the Japanese army south Saibei launched Baotou campaign. After Fu Jun attacked Baotou, the Japanese army in Mongolia invaded Suixi. From the end of January 1940 to the beginning of February, the Japanese troops were even linked to the Five Rivers, Linhe and Shaanxi. After the Japanese occupation of the fifth generation, there was a disagreement between Masahiro Okabe, Commander of the Mongolian Army and Shinichi Tanaka, chief of staff, on the issue of Wuyuan control. Okamoto advocated the implementation of the pre-war order, retreat from Wukyuan at the appropriate time; Tanaka plans to rely on the support of the Japanese military in Baotou, through the Puppet Mongolian Army, Suixi Coalition and Suixi garrison to serve as the region’s defense, which achieved The original five areas under the control of the Japanese forces purposes. This disagreement made the Fu Zuoying Army take advantage of the main force of the Japanese army to take the opportunity of successively withdrawing its former base defense area to implement the counter-offensive after achieving the goal and won the victory of the Wuyuan Campaign.