The dynasties were mostly ruled by an aristocracy whose major concern was war. The aristocracy were upper-class/noble men whose wealth is land-based and who passes power from one generation to the next. The king/emperor ruled from the capital city, and the kingdom was divided into territories governed by aristocratic military leaders, called warlords, but the king had the power to choose or remove these leaders. The land was divided into provinces and were taxed by the king in order to demonstrate their loyalty to the ruler. The king also defended the kingdom and controlled large armies, which often fought on the edges of the kingdom and claimed more land to add to the empire.