1932 Siamese coup d'état

The Siamese revolution of 1932 or the Siamese coup d'état of 1932 (Thai: การปฏิวัติสยาม พ.ศ. 2475 or การเปลี่ยนแปลงการปกครองสยาม พ.ศ. 2475) was a crucial turning point in 20th-century Thai history. The revolution, a coup d'état, was a nearly bloodless transition on 24 June 1932, which changed the system of government in Siam from an absolute monarchy to a constitutional monarchy. The "revolution" was brought about by a comparatively small group of military and civilians, who formed Siam's first political party, the Khana Ratsadon (Peoples' Party). It ended 150 years of absolutism under the Chakri Dynasty and almost 800 years of absolute rule of kings over Thai history. It was a product of global historical change as well as domestic social and political changes. It also resulted in the people of Siam being granted their first constitution.

Unlike other modern Southeast Asian states, Thailand was never formally colonised by colonial powers. Conventional perspectives attribute this to the efforts made by the monarchs of the Chakri Dynasty, particularly Rama IV and Rama V, to "modernise" the Siamese polity, and also to the relative cultural and ethnic homogeneity of the Thai nation. Rama IV (King Mongkut) opened Siam to European trade and began the process of modernisation. His son, Rama V (King Chulalongkorn), consolidated state control over the Thai vassal states and created an absolute monarchy and a centralised state. However, the success of the Chakri monarchs also sowed the seeds for the 1932 revolution and the end of the absolute monarchy. "Modernisation" mandated from above had created by the early 20th century a class of Western-educated Thais (not necessarily rooted in democratic values, with some leaning toward authoritarianism) in the commoner and lower nobility classes. These were influenced by the ideals of the French and Russian revolutions and staffed the middle and lower ranks of the nascent Siamese bureaucracy. This new elite would eventually form the People's Party that provided the nucleus of the 1932 revolution.

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