Phra Bat Somdet Phra Poramintharamaha Jessadabodindra Phra Nangklao Chao Yu Hua (), or Rama III ( 31 March 1787 – 2 April 1851), was the third monarch of Siam under the House of Chakri, ruling from 21 July 1824-2 April 1851. He succeeded his father, Buddha Loetla Nabhalai, as the King of Siam. His succession was unusual according to the traditions because Jessadabodindra was a son of a concubine not of a queen. He surpassed Prince Mongkut, who was a legitimate son of Buddha Loetla Nabhalai born to Queen Srisuriyendra.

During Jessadabodindra's reign, military hegemony of Siam could be observed through a series of massive wars in Laos, Cambodia, and Vietnam. Jessadabodindra was known for his affection of Chinese culture. As a young prince, he was also known as a great businessman who conducted profitable trades with China and enriched the royal treasury.

Early life

Prince Tub was born in 1787 to Prince Isarasundhorn and one of his concubines Chao Chom Manda Riam. Following his father's coronation in 1809, Prince Kshatriyanuchit, the surviving son of Taksin, revolted to reclaim his legitimacy. Prince Tub was assigned the task of suppressing the rebellion. He successfully accomplished his task and was praised by his father Buddha Loetla Nabhalai. Prince Tub was raised to Krom Muen Jessadabodindra and gained a great trust from the king to handle state affairs.

Jessadabodindra served his father in Krom Tha, or the Ministry of Trade and Foreign Affairs, where he developed his proficiency in foreign trades and grew his personal affection of Chinese culture. Temples later constructed by Jessabodindra was characterized by the Chinese influences in them.

Succession

As Jessadabodindra was administrating the trade affairs, his half-brother Prince Mongkut pursued the way of religion. Prince Mongkut became a monk in 1824. In that year, Buddha Loetla Nabhalai died suddenly without naming a successor. According to the traditions of royal succession, Prince Mongkut as a son of the queen was expected to succeed the throne. However, the nobility considered Prince Jessadabodindra a more competent choice as he had served the king in Krom Tha for years. The supports came strongly from the high-ranking nobility including Chao Phraya Abhay Pudhorn the Samuha Nayoke and Dis Bunnag the Minister of Krom Tha along with the Bunnag family.

Jessadabodindra finally accepted the throne and the coronation was held in 1824. His mother, Riam, was raised to Princess Mother Srisuralai. Mongkut, upon perceiving the situation, decided to remain in his ecclesiastic status to avoid the intrigues of royal politics.

The British

The First Anglo-Burmese War broke out in 1823. The British requested Siamese support in 1824. Jessadabodindra provided fleets and elephants to rush through Burmese forests. He also sent Siamese armies to participate in the invasion of Burma since the British promised Siam the conquered lands.

Phraya Chumporn ordered a massive migration out of Mergui (a common practice in Southeast Asia regarding the newly-conquered lands), which had been conquered by the British. The British were frustrated at Phraya Chumporn's actions and hostilities were heightened. Prince Jessadabodin ordered the Siamese armies to leave to avoid conflicts.

In 1825, Henry Burney arrived to negotiate peace agreements. The Burney Treaty was signed as the first treaty with the West in the Rattakosin period. Free trade was established in Siam and the taxation on foreign trading ships was greatly reduced.

Insurgency of Anouvong

The three Laotian kingdoms (Vientiane, Luang Prabang, Champasak) became Siamese tributaries after Chao Phraya Maha Kshatriyaseuk (or King Rama I, Prince Jessadabodin's grandfather) had conquered them in 1778. Anouvong, the son of the king of Vientiene, was taken to Bangkok as a captive. He spent his time in Siam for nearly thirty years and joined the Siamese forces in wars with Burma. In 1805, Anouvong returned to Vientiane to be crowned as the king.

In 1824, Buddha Loetla Nabhalai died and, in the next year, Siam was dragged into conflicts with the British Empire. Anouvong saw this as an opportunity to free his kingdom from Siamese rule. In 1825, returning from the funeral of Buddha Loetla Nabhalai in Bangkok, Anouvong captured Korat and forced the city to be evacuated. However, the Korat captives rebelled - allegedly under the supervision of Mo, wife of the ruler of Korat - although this claim is countered by many historians who indicate Lady Mo had no heroic role in the events at Tung Samrit. Anouvong then returned to Vientiane after subsequently being defeated by Thai forces. When he was later captured, Rama III had the Lao king tortured and publicly humiliated until he died.

Prince Jessadabodin sent his brother Maha Sakdi Polsep the Front Palace and Phraya Rajsupawadi to defeat the armies of Anouvong in Isan. Anouvong was defeated and fled to Vietnam. The Siamese captured Vientiane and ordered the evacuation of the city.

In 1827, Prince Jessadabodin ordered the total destruction of Vientiane. Anouvong returned to Laos with Vietnamese forces. Rajsupawadi led the Siamese to fight and the engagements occurred at Nongkai. Anouvong was defeated again and, after an attempt to flee, was captured. Vientiane was razed to the ground, extinguishing her 200-year prosperity, and ceded to be a kingdom. Anouvong was imprisoned in an iron cage in front of the Suthaisawan Hall and died in 1828.

Naming of the reigns

Since the establishment of Bangkok as a kingdom, none of the monarchs of Siam had been named properly according to the royal tradition. The Siamese called Prince Jessadabodin's grandfather the "First Reign", his father the "Middle Reign", and Jessadabodin himself the "Late Reign". The term "Late Reign" was considered inauspicious, therefore a new method of naming was created.

Jessadabodin had sculpted two Buddha statues for his father and grandfather. He then named them after their respective Buddha statues. His grandfather was given the name "Buddha Yodfa Chulaloke" after his Buddha statue, and his father "Buddha Loetla Nabhalai". Yet Jessadabodindra left his own reign unnamed until his brother Mongkut named him as "Nangklao" and created a more systematic royal nomenclature.

Revolt of Kedah

In 1837, Krom Somdet Phra Sri Suralai, mother of Jessadabodinra, died. All officials throughout the kingdom went to Bangkok to attend the funeral. At Syburi (Kedah of Malaysia now), without the presence of Siamese governors, a newphew of the Sultan of Kedah then staged a revolt. Jessadabodindra then sent Tat Bunnag down south to subjugate the rebellion quickly in 1838. Tat Bunnag then suggested the autonomy government of Kedah Sultanate. In 1839, Kedah was divided into four autonomous parts.

Vietnam and Cambodia

In 1810, the internal conflicts between the Cambodian princes forced Ang Im and Ang Duong to flee to Bangkok. Otteyraja of Cambodia turned to Gia Long of Vietnam for support against the opposing princes. However, this was perceived by Siam as treacherous as the two countries had fought for centuries over the domination of Cambodia.

In 1833, the Le Van Khoi revolt against Minh Mang broke out in Vietnam. Le Van Khoi, the rebel leader, sought Siamese helping hands. The possible war between the two countries had been commenced since Vietnamese influences in Cambodia increased. Jessadabodin intended to take this opportunity to install a pro-Siamese monarch on the Cambodian throne.

Rajasupawadi, who had been promoted to Chao Phraya Bodindecha, was assigned the mission of the capture of Saigon, with Dis Bunnag the Minister of Krom Tha commanded the fleet - to be joined at Saigon. The two Cambodian princes, Ang Im and Ang Duong, also joined the expedition. Bodindecha took Udongk and the fleet took Bantey Mas. The fleet proceeded to Saigon but was repelled.

Bodindecha then took Phnom Penh and again invaded Vietnam by land in 1842. In 1845, the Vietnamese recapture Phnom Penh but Bodindecha was able to defend Udongk. In 1847, due to Emperor Thieu Tri's policies on Christian missionaries, French forces invaded Vietnam. So the war front with Siam was negotiated. Ang Duong was installed as the Cambodian monarch with equal influences from both Siam and Vietnam, thus ending the war.

The Faithful King

200px|thumbnail|right|Rama III statue in Bangkok
King Nangklao was famous for his Buddhist faith. He fed the poor each day after becoming prince, and released animals every monastery day. More than 50 temples were built and repaired in his reign, including the first Chinese style temple at Rajaorasa, the highest stupa at Wat Arun, the Golden Mountain at Wat Sraket, the metal temple at Wat Ratchanadda, and Chetupol Temple or Wat Pho. Wat Pho is the site of the first university in Thailand.

Death and Legacy

Jessadabondin's reign saw the renewal of Western contacts. The first American mission of Andrew Jackson arrived in 1832. Dan Beach Bradley, an American physician, was the most prominent Western personality in his reign. He reformed the printing in Siam and introduced vaccination.

Jessadabodin died on 2 April 1851. Without having named a successor, the throne passed to his half-brother Prince Mongkut. Jessadabodin had many children including sons, but raised none of his consorts to queen.

There is a popular legend that Jessadabodin stated on his deathbed that "Our wars with Burma and Vietnam was over, only the threats of the Westerners was left to us. We should study their innovations for our own benefits but not to the degree of obsession or worship." This vision coincided with intense Western intervention in Siam in the reign of Mongkut. He was able to predict but not see neighboring kingdoms of; Burma and Vietnam, fell to European colonial rule. His deathbed statement shows that he had foreseen the Western threats and also expresses his sympathy towards the Europeans contrasted to most Asian rulers of his time.