The Cambodian Usurpation of 1811–1812 was when an army from Siam (Thailand) supported Ang Snguon after he overthrew his brother Ang Chan; but Vietnam sent a large army to help reinstate Ang Chan at Phnom Penh.
The Cambodian Usurpation of 1811–1812 was when an army from Siam (Thailand) supported Ang Snguon after he overthrew his brother Ang Chan; but Vietnam sent a large army to help reinstate Ang Chan at Phnom Penh. (en)