History of Bangkok in the context of "Rattanakosin Kingdom"

The Rattanakosin Kingdom, also known as the Kingdom of Siam after 1855, refers to the Siamese kingdom (in modern-day Thailand) between 1782 and 1932. It was founded in 1782 with the establishment of Rattanakosin (Bangkok), which replaced the city of Thonburi as the capital of Siam. This article covers the period until the Siamese revolution of 1932.

The kingdom governed based on the mandala system. This allows for high-autonomy locally with the kingdom influencing and effectively ruling its area of suzerainty. At its zenith in 1805 to 1812, the Kingdom was composed of 25 polities, ranging from duchies and principalities to federations and kingdoms. With the furthest extent reaching the Shan States, southern Yunnan, Laos, Cambodia, northern Si Rat Malai and Kawthoung. 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. 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.

Thonburi (Thai: ธนบุรี) is an area of modern Bangkok. During the era of the Ayutthaya Kingdom, its location on the right (west) bank at the mouth of the Chao Phraya River had made it an important garrison town, which is reflected in its name: thon (ธน) a loanword from Pali dhána 'wealth', and buri (บุรี), from púra, 'fortress'. The full formal name was Thon Buri Si Mahasamut (กรุงธนบุรีศรีมหาสมุทร 'City of Treasures Gracing the Ocean'). For the informal name, see the history of Bangkok under Ayutthaya.

In 1767, after the sack of Ayutthaya by the Burmese armies, General Taksin took back Thonburi and, by right of conquest, made it the capital of the Thonburi Kingdom, crowning himself king until 6 April 1782, when he was deposed. Rama I, the newly enthroned king, moved the capital across the river, where stakes driven into the soil of Bangkok for the City Pillar at 06:45 on 21 April 1782 marked the official founding of the new capital. Thonburi remained an independent town and province, until it was merged with Bangkok in 1971. Thonburi stayed less developed than the other side of the river. Many of the traditional small waterways, khlongs, still exist there, while they are nearly gone from the other side of the river.