The Khmers were powerful conquerors. Khmer kings commanded strong armies which marched into foreign territories and took control. Once a foreign land was under their control, Khmer kings sent governors or princes to those lands to rule over their people. They also sent tax collectors, judges, scribes, soldiers, etc., in order to enforce their laws and rule over foreigners.As discussed in a previous unit, the Khmer Empire conquered almost all of the Dvaravati Kingdom.

They established important centers in modern day Thailand, which essentially became provinces of the Khmer Empire. One of them was Phimai, in modern day Nakhon Ratchasima. The Khmers even built a very long highway from Angkor to Phimai. Along that highway were other important towns like Phanom Rung and Ta Muan. At each of these locations, impressive Khmer monuments can still be seen there today. Another important city which was captured and ruled by the Khmer Empire was Lopburi, which at that time was known as Lavo. This city was probably also connected to the ancient highway, though no archeological evidence exists as proof.