MONGKUT (1804–1868), Thai Buddhist reformer and later king of Thailand. A son of the second king of the Cakkrī dynasty (1782–), Mongkut was heir apparent to the throne. However, when his father (later known as Rama II) died before Mongkut had reached his twentieth birthday, his claims were passed over in favor of those of his uncle (Rama III). Having entered the Buddhist monastic order for a temporary stay only two weeks prior to his father's death, he decided to remain a monk. Mongkut's monastic career did not end until more than a quarter of a century later when, following his uncle's death in 1851, he was chosen to succeed to the throne. At that point he left the order, became king (Rama IV), and began a reign that continued until his death.

Mongkut began his monastic career at Wat Samorai, a forest monastery near Bangkok that was renowned for its...