or Phrachomklao or Rama IV
born Oct. 18, 1804, Bangkok, Siam
died Oct. 15, 1868, Bangkok
King of Siam (Thailand; r. 1851–68).
The 43rd child of King Rama II, he was a Buddhist monk and scholar before he ascended the throne. His reformed Buddhism grew into the Thammayut order, which today occupies the intellectual centre of Thai Buddhism. Mongkut's intellectual pursuits also brought him into contact with Western thought. As king, he fully opened Siam to Western commerce and combined tolerance and shrewdness to help ensure its survival as an independent nation. The reminiscences of an English governess employed in his household became the basis for the musical comedy The King and I .