China is divided between two empires.
The Liao dynasty, or Khitan empire, in northern China, rules over the regions of Manchuria, Mongolia, and parts of northern China proper.
The Chinese empire of the Northern Song dynasty controls most of inner China.
The Song dynasty manages through force in 975 to subdue the state now known as Southern Tang, to distinguish it from the synonymously named Tang Dynasty, as part of a series of Song conquests to reunify China.
The Song state, which had succeeded the Five Dynasties and Ten Kingdoms Period, has within two decades been able to incorporate the southern kingdoms into its realm, unifying nearly all of traditional Chinese lands.
The founding Song emperor has expanded the examination system such that most of the civil service are recruited through the exams (in contrast to the Tang where less than ten percent of the civil servants had come through exams).
He has also created academies that allow a great deal of freedom of discussion and thought: these facilitate the growth of scientific advance, economic reforms as well as achievements in arts and literature.
The founding emperor is perhaps best known for weakening the military and so preventing anyone else rising to power as he did.
