The unity of Chinese civilization under Song-era multi-polity conditions

Abstract The Song Dynasty witnessed the parallel existence of multi-ethnic polities across China. During this era, the Liao, Xixia (Western Xia), and Jin polities in the north underwent institutional transformations from tribal confederacies to dynastic systems modeled after the Central Plains tradition. They adapted their indigenous traditions by emulating the Central Plains civilization’s political systems, economic institutions, and cultural ideologies. Against the backdrop of the Song Dynasty’s abandonment of the Han–Tang era Prefecture-County (郡县) tradition—a policy retreat from direct territorial administration—the southwestern ethnic polities, while developing with relative autonomy, demonstrated institutional and cultural orientations strikingly similar to those of the northern regimes. Crucially, all these polities jointly upheld the Tianxia (天下, All-under-Heaven) cosmological order in structuring their internal governance and external relations. This widespread internalization of Central Plains civilizational norms ultimately rendered the Song’s politically fragmented period a new phase in consolidating Chinese civilizational unity.