Frontiers, or borderlands, can connote a boundary line which separates two states from one another, but refers here to a broader, more diffuse zone or place where different cultures mingle and meet. Like virtually all states before the eighteenth and nineteenth centuries, China's borders were not fixed in the modern sense, but much more fluid sites where different peoples commingled. Claims to sovereignty did not match actual administrative control, which peaked in the political center and weakened as one moved toward the peripheries. In this chapter, we view frontiers/borderlands as “permeable … and interpenetrable” spaces, zones of transition which also engendered societal transformation.

This chapter has several aims. First, it situates the northeast with respect to China's core region, the Central Plain, as a borderland which gave birth to states that borrowed from yet were not subsumed by the precocious polities of the Central Plain. In addition, it situates states in the Korean peninsula and the Japanese archipelago within the geopolitical boundary of China's northeast Asian frontier. Korean and Japanese states were created through intense interaction with other entities on the steppe and the Central Plain. The periodic crises that swept across the steppe initiated political reverberations through the northeast and the Central Plain. When these political forces collided, they sparked military clashes among China, Korea, and Japan. A brief survey demonstrates that China's historical interactions with Japan and Korea replicated every dimension of its interaction with northeast Asia. The chapter ends with the arrival of Europeans in maritime Asia, an event which disrupted and eventually shifted the power balance among these states and lifted Chinese restrictions on the movement of goods and people.

The Central Plain

The earliest historical records locate Chinese states emerging in the Yellow River drainage as it flows south and turns eastward on the borders of present-day Shaanxi, the area that historians denote as the Central Plain (zhongyuan). According to a popular contemporary encyclopedia, the capitals of these early states were clustered in the present-day province of Henan.