In the preceding chapter, I have analyzed problems in the sociopolitical structure of the Western Zhou state. Now, I turn to Zhou's relationship with the outside world and examine external pressures that may have accelerated the political disintegration of the Western Zhou state. However, this is not to offer a general survey of Zhou's foreign relations; instead, the present chapter will concentrate on a particular region, the upper Jing River valley, as the battleground between the Zhou and their northwestern enemies who had directly threatened the Zhou heartland in the Wei River valley. By focusing on one region, we will have a better chance of actually demonstrating the geopolitical crisis facing the Western Zhou state and its possible responses. The study will further enhance our understanding of the degree to which the internal and external problems had profoundly perplexed the Zhou regime.
As demonstrated in chapter 1, the Wei River valley in central Shaanxi was the heartland of the Western Zhou state and the locus of Zhou royal administration. However, if we look at a map of the Zhou realm, we find that the Zhou capitals Feng and Hao were not located in the geographical center of the Zhou state, where the eastern center Luoyi was favorably located, but were close to the western border. Through much of the dynasty, the Zhou effort to expand was focused on the east, but this could not be done without the core being secured from attacks from the west.