Thao Kam Phong ( Phra Chao Wo's son and Thao Tid Phrom ( Phar Chao Ta's son asked for assistance from King Taksin of Thonburi. In the year 1778, King Taksin sent army led by Chao Phraya Maha Kasatsuk (later became King Rama I of Bangkok to attack the city of Champasak and Vientinane