Yan Xishan
By early 1929 Feng grew dissatisfied with Chiang Kai-shek's Nationalist government in Nanjing. He joined Yan Xishan and Li Zongren to challenge Chiang's supremacy, but was defeated by Chiang in the Central Plains War. Chiang then incited anti-Yan Xishan and Feng Yuxiang sentiments among the Chinese Muslims and Mongols, encouraging them to topple their rule.