Institute of Strategic Development, Thu Dau Mot University, Binh Duong Province, Vietnam.
In the seventeenth and eighteenth centuries, Ha Tien was an important land for the ambition of three kingdoms in mainland Southeast Asia: Cochinchina (the land of Dang Trong) - Cambodia- Siam. For the Nguyen lords, Ha Tien was a strategic location for the Nguyen lords to enter the Mekong Delta, assemble the last pieces of the puzzle into the map of Dang Trong, and complete the cause of Nam Tien. For Cambodia, Ha Tien was originally a land under the management of Chan Lap, but it was only loosely managed, the country was not willing to lose Ha Tien, however, due to its weakened potential, Cambodia had to accept reality for Ha Tien to merge into Cochinchina and find an ally against Siam. For Siam, Ha Tien was located on the way to the sea, an important point on the international trade route of this period. Therefore, Ha Tien played an important role in the Eastern plan of the Siamese court.