Civilizations expand through trade, conflict, and exploration.
Civilizations expand through trade, conflict, and exploration. Usually, all three elements must be present for a civilization to grow and remain stable for a long period of time. The physical and human geography of Southeast Asia allowed these attributes to develop in the Khmer civilization. The Khmer flourished in parts of what are now Cambodia, Thailand, Laos, Vietnam, and Myanmar between 800 and 1400.