History of the Thai armed forces before 1852

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "History of the Thai armed forces before 1852" – news · newspapers · books · scholar · JSTOR (January 2021) (Learn how and when to remove this message)

Royal Armed Forces กองทัพหลวง Kongthap Luang
The Siamese army formation at the Battle of Thung lat Ya, Bangkok National Museum
Active	1238–1852
Country	Siam
Branch	Palace Guards Capital Defense Corps Artillery Corps Elephantry Corps Cavalry Corps Infantry Regiments Navy
Type	Royal Siamese Army Royal Siamese Navy
Role	Military force
Size	100,000+ (1765) 70,000 (1785) 200,000+ (1800)
Engagements	Burmese–Siamese wars Siamese–Cambodian War (1591–1594) Siamese–Vietnamese wars Anglo-Siamese War Siege of Bangkok Lao rebellion (1826–1828)
Commanders
Notable commanders	Ramkhamhaeng, Naresuan, Taksin, Bodindecha

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.

The Royal Thai Armed Forces are the contemporary military of Thailand.