Abstract: Two labels of particularity can wisely describe recent progresses in medieval Chinese political history, which is “stagnated horizontally” and “expanded horizontally”. Since the traditional paradigms with a focus on “political group” or “clannish division” has become the bottleneck of political history studies, by introducing the concept of social network, I advanced the compound structure of “politics-patron” in political activities. This improved traditional paradigm of analysis on political groups. Also, the introduction of two new perspectives “political process” and “political culture”, expand research themes of political history. Moreover, the rise of “New History” also forcefully challenged the basic research unit of “event” in political history. Therefore, we should revisit traditional historiography, thus to discover and reveal the “critical juncture” by reconstructing causal relationship as well as causal inference in historical studies. Only by these means can we re-implement legitimacy on “event history” .