King Bodawpaya of Burma pursued an ambitious campaign to expand his dominions into the lands of the former Ayutthaya Kingdom. His armies attacked Lanna in northern Siam, where Kawila, Prince of Lampang, put up a brave fight and delayed the Burmese advance, all the while waiting for reinforcements from Bangkok. When Phitsanulok was captured, Anurak Devesh the Rear Palace, and Rama I himself led Siamese forces to the north. The Siamese relieved Lampang from the Burmese siege.