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.
The Thai economy is the world's 20th largest by GDP at PPP and the 27th largest by nominal GDP.
It became a newly industrialised country and a major exporter in the 1990s.
(198,000 sq mi), Thailand is the world's 50th-largest country.