Thailand distinguished itself from other Southeast Asian states in the nineteenth century as the only kingdom that survived the aggressive thrust of the New Imperialism. Among the significant factors that helped Thailand preserve its independent identity were its geographical location, its able diplomacy, and its policy of modernization. Although some credit for Thailand’s independent status may rightly be given to the Anglo-French desire to avoid a common frontier and, therefore, to keep Thailand as a buffer state, a considerable share of the credit is owed to the policies of two remarkable Thai monarchs: Rama IV, or Mongkut (1851–1868), and Rama V, or Chulalongkorn (1868–1910). Together, they brought about a fair measure of modernization, revolutionary in the context of Thailand of those times. They successfully used diplomacy, playing the British against the French and losing some of the Thai territories to both, but preserving the core of the kingdom where the ethnic Thais lived.