<P> Thailand (/ ˈtaɪlænd / TY - land or / ˈtaɪlənd / TY - lənd; Thai: ประเทศไทย, rtgs: Prathet Thai, pronounced (prathêːt thaj) (listen)), officially the Kingdom of Thailand (Thai: ราช อาณาจักร ไทย, rtgs: Ratcha - anachak Thai (râːtt͡ɕhaʔaːnaːt͡ɕàk thaj) (listen)), formerly known as Siam (Thai: สยาม, rtgs: Sayam (sajǎːm)), is a country at the centre of the Indochinese peninsula in Southeast Asia . </P> <P> The country has always been called Mueang Thai by its citizens . By outsiders prior to 1949, it was usually known by the exonym Siam (Thai: สยาม rtgs: Sayam, pronounced (sajǎːm), also spelled Siem, Syâm, or Syâma). The word Siam has been identified with the Sanskrit Śyāma (श्याम, meaning "dark" or "brown"). The names Shan and A-hom seem to be variants of the same word . The word Śyâma is possibly not its origin, but a learned and artificial distortion . Another theory is the name derives from Chinese: "Ayutthaya emerged as a dominant centre in the late fourteenth century . The Chinese called this region Xian, which the Portuguese converted into Siam ." (Baker and Phongpaichit, A History of Thailand, 8) A further possibility is that Mon - speaking peoples migrating south called themselves' syem' as do the autochthonous Mon - Khmer - speaking inhabitants of the Malay Peninsula . </P> <P> The signature of King Mongkut (r . 1851--1868) reads SPPM (Somdet Phra Poramenthra Maha) Mongkut King of the Siamese, giving the name "Siam" official status until 24 June 1939 when it was changed to Thailand . Thailand was renamed to Siam from 1946 to 1948, after which it again reverted to Thailand . </P> <P> According to George Cœdès, the word Thai (ไทย) means "free man" in the Thai language, "differentiating the Thai from the natives encompassed in Thai society as serfs ." A famous Thai scholar argued that Thai (ไท) simply means "people" or "human being", since his investigation shows that in some rural areas the word "Thai" was used instead of the usual Thai word "khon" (คน) for people . </P>

When did siam change its name to thailand
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