The thesis examines the political factors in the structure of power in North China and the chief changes in this structure during the first half of the tenth century. The greater part of this period was dominated by the military governors and the administrators and army officers of their provinces. Through a survey of the main changes in North China, the thesis attempts to show that a) a number of ex-governors who had seized the throne laid the foundations of a new imperial court based on the organisation of their provincial governments, b) decisive changes occurred in the period 926-946 and c) the Emperor's Army which was established to deal with powerful governors became the basis of a new structure of power.