The Rattanakosin Kingdom was founded in 1782 with the establishment of Rattanakosin (Bangkok), which replaced the city of Thonburi as the capital of Siam. The maximum zone of influence of Rattanakosin included the vassal states of Cambodia, Laos, Shan States, and the northern Malay states. The kingdom was founded by Rama I of the Chakri Dynasty. The first half of this period was characterized by the consolidation of Siamese power in the center of Mainland Southeast Asia and was punctuated by contests and wars for regional supremacy with rival powers Burma and Vietnam.^[56] The second period was one of engagements with the colonial powers of Britain and France in which Siam remained the only Southeast Asian state to maintain its independence.^[57]

Internally the kingdom developed into a centralized, absolutist, nation state with borders defined by interactions with Western powers. The period was marked by the increased centralization of the monarch's powers, the abolition of labor control, the transition to an agrarian economy, the expansion of control over distant tributary states, the creation of a monolithic national identity, and the emergence of an urban middle class. However, the failure to implement democratic reforms culminated in the Siamese revolution of 1932 and the establishment of a constitutional monarchy.