Thonburi Kingdom
The Royal Siamese Armed Forces (Thai: กองทัพหลวง) were the armed forces of the Thai monarchy from the 12th to 19th centuries. The term refers to the military forces of the Sukhothai Kingdom, the Ayutthaya Kingdom, the Thonburi Kingdom and the Early Rattanakosin Kingdom in chronological order. The army was one of the major military forces of Southeast Asia. With a reform into a new Western-style army in 1852, the Royal Siamese Army became a new European-trained military force.