The doom of the Later Han northwestern military elite was spelt, however, long before Ma Chao's tragic end. When Dong Zhuo moved the imperial capital from Luoyang to Chang'an, the northwestern powers kept a distance from him and maintained a fragile balance between the two sides. The murder of Dong in 192 CE, however, set off a power struggle among the northwestern military strongmen and threw the region into chaos again. The northwestern borderlands were always a restive region in imperial China. As a frontier region of the Qin-Han empire, the northwest constituted a new territory to the Chinese realm. Until the Later Han times, some portions of the northwestern region had only been part of the imperial realm for 100 years. Comparing and contrasting the varying conditions of the militarization of different frontiers of the Later Han empire will also provide important insights into the understanding of the emergence of great disunion in early medieval China.