Chey Chettha IV[1] (1656–1725), born Ang Sor, was a Cambodian king for several periods in Cambodia's history (r. 1675–1695, 1696–1700, 1701–1702, 1705–1706).
Vietnamese army attacked Phnom Penh, the king Kaev Hua II fled into forest.
[3] In 1688, Dương Ngạn Địch, a Chinese adventurer and also a general of Nguyễn lord, was murdered by Hoàng Tiến (黃進).
Using this excuse, Chey Chettha IV started to building fortifications and did not pay tribute to Nguyễn lord.
The vice king (uparaja) Ang Em (Barom Ramadhipati) surrendered to Vietnamese, and ascended the throne.
A Vietnamese army under Trần Thượng Xuyên and Nguyễn Cửu Phú (阮久富) was sent to Cambodia to help Ang Em.