Suiyuan Campaign

The Suiyuan Campaign was an engagement between the National Revolutionary Army of the Republic of China and the Japanese-trained Inner Mongolian/Grand Han Righteous Armies before the outbreak of official hostilities during the Second Sino-Japanese War.

Background
The Tanggu Truce of 1933 established a ceasefire between the Imperial Japanese Army and the Kuomintang National Revolutionary Army, including a demilitarized zone running from the coast at Tianjin to Beijing. As neither the Empire of Japan nor the Republic of China wanted to break the truce overtly, the center of conflict shifted west to Inner Mongolia, where proxy armies were used by both sides over the provinces of Chahar and Suiyuan.

During the 1933-1936 period, Chahar proclaimed itself the independent Mongol Military Government allied with Japan under Prince Demchugdongrub who sought to rule all of Inner and Outer Mongolia and parts of northern China.

History
On 14 November 1936, a coalition of the Inner Mongolian Army's 7th and 8th Cavalry Divisions, Wang Ying's Grand Han Righteous Army, and Mongol mercenaries from Jehol, Chahar and other areas, supported by 30 Japanese advisors, attacked the Chinese garrison at Hongort.

After several days of fighting the attackers failed to capture the town. On 17 November, a Chinese counterattack surprised the invaders and led to a disorganized retreat. Taking advantage of the Mongolian disorder General Fu Tso-yi made a flanking movement to the west of the Mongolian headquarters at Pai-ling-miao and attacked, capturing it and routing the Mongolian forces, who suffered 300 killed, 600 wounded, and 300 captured. Wang and his Grand Han Righteous Army were trucked into a location near Pai-ling-miao and launched a counterattack, which failed dismally on 19 December, with most of the attackers either taken prisoner or annihilated.

Small scale fighting continued in Suiyuan until the beginning of open hostilities following the Marco Polo Bridge Incident the following year.

Aftermath
The defeat of Japan’s proxy forces encouraged many Chinese into pushing for a more active resistance against the Japanese. The Xi'an Incident which occurred immediately after the successful outcome of this campaign was possibly triggered by this event.

Small scale combat continued in Suiyuan until the beginning of open hostilities following the Marco Polo Bridge Incident the following year. Following his defeat in Suiyuan, Prince Demchugdongrub was forced to rebuild his army. With Japanese help by the time war broke out in July 1937, his army consisted of 20,000 men in eight cavalry divisions. These forces participated in Operation Chahar and the Battle of Taiyuan during which Japanese regular and allied Inner Mongol forces finally captured eastern Suiyuan province.

Topographic maps

 * Wu Chuan nk49-8 Pai-ling-miao, Wu Chuan area of Suiyuan Province
 * Chi-Ning nk49-9 T'ao-Lin(Hongge'ertu), Shengdu, Suiyuan - Chahar border