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 Thai economy is the world's 20th largest by gross domestic product (GDP) at PPP), is a country at the centre of the Indochinese peninsula in Southeast Asia.The country has always been called Mueang Thai by its citizens.Following the decline and fall of the Khmer empire in the 13th–15th century, the Buddhist Tai kingdoms of Sukhothai, Lanna, and Lan Xang (now Laos) were on the rise.However, a century later, the power of Sukhothai was overshadowed by the new Kingdom of Ayutthaya, established in the mid-14th century in the lower Chao Phraya River or Menam area.Similar to other regions in Southeast Asia, Thailand was heavily influenced by the culture and religions of India, starting with the Kingdom of Funan around the 1st century CE to the Khmer Empire.Indian influence on Thai culture was partly the result of direct contact with Indian settlers, but mainly it was brought about indirectly via the indianized kingdoms of Dvaravati, Srivijaya, and Cambodia.
The Burmese–Siamese War (1765–1767) left Ayutthaya burned and sacked by King Hsinbyushin Konbaung.The Thai National Anthem (Thai: ), written by Luang Saranupraphan during the extremely patriotic 1930s, refers to the Thai nation as: prathet Thai (Thai: ประเทศไทย).The first line of the national anthem is: prathet thai ruam lueat nuea chat chuea thai (Thai: There is evidence of human habitation in Thailand that has been dated at 40,000 years before the present, with stone artifacts dated to this period at Tham Lod Rockshelter in Mae Hong Son.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. 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.According to George Cœdès, "The Thai first enter history of Farther India in the eleventh century with the mention of Syam slaves or prisoners of war in" Champa epigraphy, and "in the twelfth century, the bas-reliefs of Angkor Wat" where "a group of warriors" are described as Syam.Additionally, "the Mongols, after the seizure of Ta-li on January 7, 1253 and the pacification of Yunnan in 1257, did not look with disfavor on the creation of a series of Thai principalities at the expense of the old Indianized kingdoms." The Menam Basin was originally populated by the Mons, and the location of Dvaravati in the 7th century, followed by the Khmer Empire in the 11th.Western influence nevertheless led to many reforms in the 19th century and major concessions, most notably the loss of a large territory on the east side of the Mekong to the French and the step-by-step absorption by Britain of the Shan and Karen people areas and Malay Peninsula.As part of the concessions which the Chakri dynasty offered to the British Empire in return for their support, Siam ceded four predominantly ethnic-Malay southern provinces to the British Empire in the Anglo-Siamese Treaty of 1909.(198,000 sq mi), Thailand is the world's 50th-largest country.It is the 20th-most-populous country in the world, with around 69 million people.