Nam tiến

Nam tiến (Vietnamese: [nam tǐən], lit. "southward advance" or "march to the south") refers to the southward expansion of the territory of Vietnam from the 11th century to the mid-18th century. The territory of Vietnam was gradually expanded to the South from its original heartland in the Red River Delta. In a span of some 700 years, Vietnam tripled its territory in size and more-or-less acquired its elongated shape of today.

The direction of expansion to the south could be explained by geographic and demographic factors. With the South China Sea to the east, the Truong Son Mountains to the west, and China to the north, the Vietnamese polity pushed south, following the coastal plains. The 11-14th centuries saw battle gains and losses as the frontier territory changed hands between the Viets and Chams. The 15-17th centuries following the failed Ming conquest (1407-1420), the resurgent Viets took the upper hand, defeating the less-centralized state of Champa, forcing the cession of more land. By the 17-19th centuries, Vietnamese settlers had penetrated the Mekong Delta. The Nguyen Lords of Hue by diplomacy and force wrested the southernmost territory from Cambodia, completing the "March to the South".

The native inhabitants of the Central Highlands are the Degar (Montagnard People) peoples. Vietnam conquered and invaded the area during its "march to the south" (Nam tiến).

Cham provinces were seized by the Nguyen Lords. Provinces and districts originally belonging to Cambodia were taken by Vo Vuong.

Cambodia was constantly invaded by the Vietnamese Nguyen Lords. Around a thousand Vietnamese were slaughtered in 1667 in Cambodia at the hands of Taiwanese. The Khmer inhabited Mekong Delta started to become inundated with colonizing Vietnamese and in response the Vietnamese were subjected to Cambodian retaliation. The Cambodians told Catholic European envoys that the Vietnamese persecution against Catholics justified retaliatory attacks launched against the Vietnamese colonists.

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Wikipedia