Manzhouguo: The True Story of a Shortlived, Ideal State ...
During that conflict, there were series of advances and retreats in the theaters of Shanhaiguan, Zhaoyang and Rehe. However, the Northwest Army (led by Feng Yuxiang, commander of the 3rd Division of the offensive forces) suddenly shifted its loyalties to Zhang Zuolin''s Fengtian Army, returned to Beijing and attempted a coup d''etat.