Kingdom of Vientiane
As a first step toward a war with the Siamese, Hsinbyushin decided to secure the northern and eastern flanks of Siam. In January 1765, a 20,000-strong Burmese army led by Ne Myo Thihapate based in Chiang Mai invaded the Laotian states. The Kingdom of Vientiane agreed to become Burmese vassal without a fight. Luang Prabang resisted but Thihapate's forces easily captured the city in March 1765, giving the Burmese complete control of Siam's entire northern border.