Interesting topic, but bad writing, wild claims/speculation stated as fact, and a few instances of rather overbearing CCP nationalism (i.e. insisting that the Khitan fleeing West after the collapse of the Liao dynasty was "the expansion of 'Chinese' culture ["中華文化"]") make it more of a chore to read than it should have been. Which is a shame.
In fact the Liao culture was barely touched upon at all, it's essentially a mostly (mostly :|) chronological history of the rulers and their mostly untimely demises.