Siamese invasion of Patani (1786)

The Siamese invasion of Patani occurred as part of the expansion and unification of the Siamese kingdom during the reign of King Buddha Yodfa Chulalok the Great (Rama I) of the Rattanakosin period Siam led an army to attack Pattani until it was defeated, with Prince Maha Sura Singhanat as the commander. Pattani lost its independence at this time.

Source: Wikipedia — Siamese invasion of Patani (1786) (CC BY-SA 4.0)