The Lower Mekong Region or Mekong Delta:
Funan Kingdom – covered the areas which today are Cambodia; southern Vietnam; northeastern Thailand, and some parts of the Chao Phraya Basin, southern Thailand , and the Malay Peninsular.
Chenla Kingdom – located in what today are Cambodia, Laos, northern Vietnam, and northeastern Thailand.
Khmer Kingdom – Its power (through political & cultural domination) expanded from what today is Cambodia to domains of neighboring kingdoms.