Siam' (native name Muang Thai, 'the Land of the Free') occupies the central portion of the Indo-China Peninsula, stretching from 4° in the Malay Peninsula to Chiengsen (20° 22' N.), on the river Mekong, or a distance of nearly 1100 miles; greatest breadth, 750 miles. The main body of it lies between Burma (British), the Shan States (partly Siamese), and French Indo-China (Cambodia and Annam). In 1893 the French advanced their Annamese frontier to the Mekong, as far north at least as 18° N. The territory ceded to France was about 50,000 sq. m., with a pop. of 100,000. The area of the kingdom of Siam is now about 250,000 sq. m. (60,000 in the Malay peninsula); and the pop., which is concentrated principally in Bangkok and the Menam Valley, is estimated at about 12,000,000, of whom possibly 3,000,000 are Chinese. The Malay Peninsula excluded, the plain of the Menam Valley, the adjoining eastern coast, and the Korat plateau (from 400 to 1000 feet high) occupy the greater portion of the country. These plains are fringed by hills up to 5000 feet high, and the north generally is hilly. The Menam, with a course of 600 miles, is the principal river. Two other streams, the Meklong and the Bangpakong, flow into the Gulf of Siam. The Mekong (q. v.) has the main part of its course in or along Siamese territory, but navigation for vessels of any size is impeded by rapids. The rivers form the principal trade-routes, and in and around Bangkok there is an intricate network of canals. Only the land adjoining the rivers is under cultivation, and the greater portion of the country is covered by pathless jungle. The climate is considered healthy for the tropics; low malarial fever is the most frequent illness amongst the European community. There are two seasons - the wet and the dry, the former lasting from May till November. The average temperature for the year is 81°; the greatest heat in April should not exceed 94° in a well-made house.

The chief production of Siam is rice. It is the national food, and its export forms the great source of wealth of the country, making two-thirds of the total exports, which amount to between 4,000,000 and 5,000,000. The other principal exports are teak-wood, obtained in the north, pepper, salt, and dried fish, cattle (for consumption in Singapore), and til (sesame) seed. Goods are imported to the value of about 3,500,000, comprising treasure and gold-leaf, cotton manufactures and China goods, jewellery, and opium. The foreign trade is mainly with Singapore, Hong-Kong, and Britain. The principal commerce of the capital is in the hands of Chinese; the labour market is supplied by Chinese coolies, and the best tradespeople and artisans are Chinese. The native Siamese confine themselves to agriculture, fishing, boating, and petty hawking, and many are simply idle hangers-on of the nobility. In addition to the exports, the country produces hemp, tobacco, cotton, coffee, cardamoms, and tropical fruits.

The wild elephant, tiger, bear (in the north), wild pig, deer, monkey, and squirrel abound in the distant jungles. Tame elephants are employed. Specimens of the famous 'white elephant' are kept in the courtyard of the royal palace at Bangkok, but are not regarded with any special veneration. Crocodiles are found at the mouths of the rivers. The python, cobra, reptiles of various kinds, mosquitoes, ants, fireflies, and tropical insects are plentiful. There are many species of birds, and the rivers and coast swarm with excellent fish. Gold has been produced in Siam from time immemorial; and argentiferous copper also is found. Alluvial tin-mines are worked by Chinese in the Malay peninsula, and iron is turned out in the north by native smelters. Rubies and sapphires are found in the Chantaboon district (occupied by France in pledge of the fulfilment of the treaty of 1893). The only manufactures are coarse cloth and silk, rough paper made from bark, water-jars, and coloured tiles for the roofs of temples.

Pure Siamese are estimated to number only a third of the total population. The north and east are occupied by Laos or Shans, and besides the Chinese there are numbers of immigrant Burmese, Indians, Malays, and Cambodians. The character of the Siamese is essentially peaceful and indolent; they are very social, vain, and fond of bright dresses and jewellery. The houses are built of wood or bamboo, thatched with the leaf of the attap palm, and are raised a few feet from the ground on piles. Both sides of the river at Bangkok (q.v.) are lined for several miles with houses floating on wooden pontoons or on bundles of bamboo. Every Siamese, with certain exceptions, is bound to give the state free labour for about three months in the year, and to supply travelling officials with provisions and means of transport. The religion of the country is Buddhism. The sacred books are written in Pali in the Cambodian character. The old system of first and second kings has been abolished. The legislative power is vested in the king, in conjunction with a council of ministers and a council of state. There is a small permanent army, and the navy consists of a few tiny gunboats. The revenue of the country averages about 2,500,000, and includes 870,000 from the farmers of the sale of opium and spirits, and the keepers of gambling and pawnbroking houses; 1,0S6,000 from taxes on forests and mines, posts, telegraphs, and railways, capitation tax, land-tax, and fisheries, etc.; and 275,000 from customs. Since 1890 the government has made many reforms in administration. The civil list has been put on a definite footing; taxation has been lightened and simplified. Sanitation, education, and the administration of law and justice are all greatly improved. Railways are being extended (330 miles were open in 1905); the postal and telegraph systems have been developed; Bangkok has a telephone exchange and electric lighting and tramways. Education, carried on by the priests, is supplemented by schools for the teaching of English. Foreigners are subject only to their own laws, administered by consuls.

Ayuthia (q.v.), founded in 1350, remained the capital till 1768, when it was taken by the Burmese, Bangkok next year becoming the capital. Cambodia was conquered in 1532. In 1893 the French dictated a treaty granting themselves a largo slice of Siamese territory. See books by Pallegoix(1854), Bowring(1857), Colquhoun (1885), Coit (1886), Hallett (1889), J. Anderson (1890), Grindrod(1896),Warrington Smyth (1898), Young (1900), Vincent (1900), and Campbell (1902).