Siam regained strength under the Thonburi Kingdom, led by Taksin, after freeing itself from Burmese occupation. After repelling another large-scale Burmese invasion, the Rattanakosin Kingdom (Chakri dynasty) led by Rama I, as the successor of the Thonburi Kingdom, turned its attention to its insubordinate southern Malay subjects, fearing renewed attacks from Burma along the western seaboard of the Malay Peninsula. Attention to the south was also needed because of disunity and rivalries among the various southern tributary sultanates, stemming from personal conflicts and a reluctance to submit to Siamese authority. One example of this resistance was the Sultanate of Pattani under Sultan Muhammad, who refused to aid Siam during the Siamese war of liberation. This led Rama I's younger brother, Prince Surasi, to attack Pattani in 1786. Many Malays were killed, and survivors were taken to the Siamese stronghold in Bangkok as slaves. Siam's subjugation of Pattani served as a direct warning to the other Malay tributary states, particularly Kedah, they too having been forced to provide thousands of men, and food supplies, throughout the Siamese resistance campaign against the Burmese.