In 1824, Phutthaloetla Naphalai died and, in the following year, Siam was dragged into conflicts with the British Empire. Anouvong saw this as an opportunity to wield his power. In 1825, returning from the funeral of Phutthaloetla Naphalai in Bangkok, Anouvong assembled a large force and went on the offensive. After defeating Bangkok-vassal principalities along the way, Anouvong captured Korat, the main defensive stronghold of Siam in the northeast. He forced the city to be evacuated while marching to Saraburi, on approach to the capital, Bangkok. However, the Korat captives rebelled—said to have been at the instigation of Lady Mo, wife of a ruling noble of Korat—although this claim is countered by many historians who say Mo had no heroic role in the events at Tung Samrit, though a contemporary account did mention her action. As Bangkok gathered counterattacking troops, Anouvong withdrew to return to Vientiane.