Phra Bat Somdet Phra Poramenthramaha Mongkut Phra Chom Klao Chao Yu Hua (Thai: พระบาทสมเด็จพระปรเมนทรมหามงกุฎฯ พระจอมเกล้าเจ้าอยู่หัว), or Rama IV, known in foreign countries as King Mongkut (18 October 1804 – 1 October 1868), was the fourth monarch of Siam (Thailand) under the House of Chakri, ruling from 1851-1868. As the king of Siam, Mongkut urged his royal relatives to have “a European-style education.” The missionaries, as teachers, taught modern geography and astronomy, among other subjects. Six years after Mongkut’s death, the first Thai geography book was published in 1874, called Phumanithet by J.W. Van Dyke. However, geography was only taught in some schools, mainly those that were run by American missionaries with English programs for upper secondary students. Thongchai Winichakul argues that Mongkut’s efforts to popularize Western geography helped bring reform to education in Siam.