Sun Dianying

Campaigns in Inner Mongolia

In early 1933, the Imperial Japanese Army launched Operation Nekka to conquer Rehe Province. At the time, Sun commanded the 41st Army of 30,000 men, most of them garrisoned in Lingyuan; one of the soldiers under his command during this conflict was writer Duanmu Hongliang. As the Japanese closed in on Lingyuan, Sun did not resist, as he and his sub-commanders had been bribed by the invaders. They allowed the Japanese to occupy the city almost without resistance. Only a few units under Sun's command refused to retreat from Lingyuan and fought the Japanese to the death, while he moved his army to Chahar Province. As the entire Chinese defense of Rehe collapsed, some of Sun's units lost contact to their headquarters and were left behind; one of his regiments consequently launched a counter-attack on Chifeng, not knowing that other NRA forces had already fled the province. As the Chinese high command initially refused to admit that Sun had been bribed, and some troops under his command had valiantly fought the Japanese, Sun's reputation was slightly rehabilitated in course of the campaign, an opportunity he seized to expand his strength. At the time of the Tanggu Truce, Sun's troops garrisoned the strategic Beijing–Suiyuan Railway.

In May 1933, with Feng Yuxiang organizing the Chahar People's Anti-Japanese Army, Sun also advocated opposition to Japan and criticized Chiang Kai-shek's central government, yet protested his loyalty to Chiang. The national government feared Sun Dianying would cooperate with Feng's Anti-Japanese Army, allowing them to use the railroad to support their forces. However, Sun was also not willing to be involved in a conflict with Chiang. He hoped to be involved in northwest development and control a territory of his own there. In mid-June, when Chiang ordered Sun's army to leave the railroad garrison and open up wasteland in Qinghai, he was willing to go. Chiang's troops replaced his in July, cutting off the Anti-Japanese Army from communication with the rest of China.

Chiang intended the allied northwest Ma clique to have the strength to cope with Sun Dianying and to weaken themselves while competing with him. As the Ma warlords saw through this plot, and strongly protested against Sun moving into their territories, Chiang was forced to give in. He ordered Sun to halt his advance through Suiyuan province in November 1933. However, Sun's forces became short of food and restive from their inactivity.

In January 1934 with his forces threatened with starvation and talk of mutiny, Sun Dianying was forced to march his 60,000-man army west from Suiyuan province into Ningxia, governed by Ma Hongkui. Supported by his fellow Ma warlords Ma Hongbin, Ma Bufang, and Ma Buqing, Hongkui resisted, starting a war for Ningxia. Both sides battled for three months, with heavy losses. In March, Sun's army was defeated by the Ma forces, while his route of retreat was cut off by Yan Xishan and troops loyal to Chiang Kai-Shek. He consequently surrendered in April, and went to Taiyuan to live in seclusion, while the remnants of his defeated troops were incorporated into Yan Xishan's provincial forces. Just one month later, however, Sun was appointed "high military advisor" for the Military Affairs Commission's Beiping branch by the central government.

Second Sino-Japanese War In 1937, when the Second Sino-Japanese War erupted, Sun resurfaced once again, commanding troops against the Japanese, taking command of the Hebei-Chahar Guerillas in 1938. He was eventually appointed as general of the NRA's 5th Army, but later on defected to the Japanese in 1943. Joining Wang Jingwei's Reorganized National Government of the Republic of China, he was given command of the Collaborationist Chinese Army's 6th Group Army District which guarded the southern Beijing–Hankou railway, and was made a member of its National Military Council. In August 1943 his troops were defeated by PLA forces in the Linnan Campaign.

When the Second Sino-Japanese War was over, Sun participated in the Chinese Civil War on the side of the Nationalists. He was eventually defeated by People's Liberation Army forces and taken prisoner. In 1946 or 1947, he died in the POW camp of Wu'an.