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Rama IV(räm`ə), 1804–68, king of Siam, now Thailand (1851–68). A devout Buddhist monk, he was displaced in succession to the throne by his brother, who ascended as Rama III. Mongkut became king as Rama IV in 1851, and then used his knowledge, especially of the West, accumulated during his long years of study, to further his country's interests. He established diplomatic relations with several European countries and the United States, opened Siam to Western trade, and undertook extensive internal reform in all fields. Because of these measures, Siam was the only country in Southeast Asia not to fall under Western control in the 19th cent. He was succeeded by his son ChulalongkornChulalongkorn
or Rama V
, 1853–1910, king of Siam (1868–1910). Educated in part by a British governess, Anna Leonowens, and an English tutor, he greatly advanced the Westernization of Siam (present-day Thailand) begun by his father, King Mongkut.
..... Click the link for more information. . Mongkut was made famous in the West by Margaret Landon's book Anna and the King of Siam (1944), which was based on the reminiscences of Anna Leonowens, a British governess at the court of Siam.