The only country 
in Southeast Asia to remain independent during the colonial period, and until 1939 officially known as “Siam” (now Muang Tai, “Land of the Free,” or Pratet Tai, “Free Kingdom”), Thailand has been strongly influenced by both China and India but is fundamentally a sub-Indian civilization, based on Buddhism and using a version of the Devanagari (Sanskrit) alphabet, 
adapted from Cambodian. A Buddhist historical Era is still used in Thailand. In fighting with Vietnam for influence over Cambodia and Laos, the Vietnamese were not even regarded as properly Buddhist, because of the more Confucian basis of Vietnamese government.
Nevertheless, Siam was more closely in contact with China than with India, has long been the home of a large Chinese community, and in 1575 even requested a new royal seal from China, to replace the one lost to the Burmese in 1569. So we really have a phenomenon of Indian and Chinese cultural spheres overlapping. It is noteworthy that both Laos and Cambodia were vassals of the original Bangkok kingdom but were lost to the French colonial empire in Vietnam.
The flag of Siam was originally a white elephant on a red background. However, in 1916 King Vajravudh was touring a flooded region and saw the flag flying upside down as a distress signal. Since he didn’t like the 
idea of the national flag being used in that way, he designed a new flag that was symmetrical and would not look different if turned from top to bottom. The new flag was adopted 28 September 1917.
Siam was an ally of Japan in World War II, with the Japanese building a infamous railway overland into Burma, using mistreated Allied prisoner-of-war labor. No one, however, believed that this “alliance” was at all voluntary on the part of the Thais, and the Kingdom, freed from Japanese occupation, was unmolested by the Allies after the War.
By the 1990’s, Thailand economically was looking rather like one of the Asian Tigers. It stumbled in the Asian recession but now seems back on track. By 2003, according to The Economist, Thailand was the 31st largest economy in the world, but 22nd in “purchasing power parity” (adjusting for local prices, etc.). Thailand’s gross domestic product per capita was $2,010, but this translated into $6,320 in purchasing power parity, 18.5% of the United States, making it the 66th richest economy in the world, about the level of Romania, Columbia, and Tunisia. This is not quite in the league of the Four Tigers (Hong Kong, 12th; Singapore, 16th; Taiwan, 24th; and South Korea, 34th), but the Thais do seem to have the kind of restlessness and enterprise that bodes well. On the other hand, Thailand is infamous for its prostitution and sex trade. This can be disturbing enough, especially where children are concerned, but the problem is now compounded by the spread of AIDS. This not only threatens the sex business, as a large source of foreign tourism, but it also threatens the future of the country as large numbers of people only peripheral to the sex trade become infected. How the Thais cope with this is one of the most important national questions as the new century begins.
| Kings of Sukhothai | |
|---|---|
| Sri Indraditya | c.1240-c.1270 |
| Ban Müang | c.1270-c.1279 |
| Ramkhamhaeng | c.1279-1298 |
| institution of Thai alphabet, by 1283 | |
| Lö Thai | 1298-1346/7 |
| Ngua Nam Thom | 1346-1347 |
| Mahathammaracha I Lüthai |
1346/7-1368/74? |
| Mahathammaracha II | 1368/74?-1398? |
| Mahathammaracha III Sai Lüthai |
1398-1419 |
| Mahathammaracha IV | 1419-1438 |
| Conquered by Adudhya, 1438 | |
| THE BUDDHIST HISTORICAL ERA |
543 BC |
|---|---|
| 2000 AD + 543 = 2543 Annô Buddhismi |
|
| Kings of Lan Na | |
|---|---|
| Mangrai | 1259-1317 |
| Chai Songkhram | 1317-1318 |
| Saen Phu | 1318-1319, 1324-1328 |
| Khrüa | 1319-1322 |
| Nam Thuam | 1322-1324 |
| Kham Fu | 1328-1337 |
| Pha Yu | 1337-1355 |
| Kü Na | 1355-1385 |
| Saen Müang Ma | 1401-1441 |
| Sam Fang Kaen | 1401-1441 |
| Tilokaracha | 1441-1487 |
| Yot Chiang Rai | 1487-1495 |
| Müang Kaeo | 1495-1526 |
| Ket Chettharat | 1526-1538, 1543-1545 |
| Chai | 1538-1543 |
| Queen Chiraprapha | 1545-1546 |
| Setthathirat | 1546-1551 |
| Queen Thao Mae Ku | 1551 |
| Mekuti | 1551-1564 |
| Burmese conquer Chiang Mai, 1558 | |
| Queen Wisutthithewi | Burmese control, 1564-1578 |
| Burmese Tharawaddy Prince |
1578-1607 |
| [2 sons of previous?] | 1607-1613 |
| Thadogyaw | 1613-1615 |
| Si Song Müang | 1615-1631 |
| Phraya Thipphanet | 1631-1659 |
| [ruler of Phrae] | 1659-1672 |
| Ingsemang, Burmese | 1672-1675 |
| Chephutarai, Burmese | 1675-1707 |
| Mangraenara, Burmese | 1707-1727 |
| Thep Sing, rebel | 1727 |
| Ong Kham | 1727-1759 |
| Chan | 1759-1761 |
| Khi Hut | 1761-1762 |
| Burmese conquer Chiang Mai, 1763 | |
| Abhayagamani, Burmese |
1768-1771 |
| Moyagamani, Burmese |
1768-1771 |
| [revolt] | 1771-1774 |
| Conquered by Thonburi, 1774, 1776 | |
| Chao of Chiang Mai, Vassals of Thonburi & Bangkok |
|
|---|---|
| Kavila | 1781-1813 |
| Thammalangka | 1813-1821 |
| Kham Fan | 1821-1825 |
| Phutthawong | 1825-1846 |
| Mahawong | 1846-1854 |
| Kavilorot | 1856-1870 |
| Intanon | 1871-1897 |
| Suriyawong | 1901-1911 |
| In Kaeo | 1911-1939 |
| Kings of Bangkok, Chakri Dynasty |
|
|---|---|
| Phra Phutthayotfa, Rama I | 1782-1809 |
| Penang ceded to Britain by Sultan of Kedah, 1785; Burmese Invasion Defeated, 1785 |
|
| Phra Phutthaloethla, Rama II | 1809-1824 |
| Phra Nangklao, Rama III | 1824-1851 |
| Mongkut, Rama IV | 1851-1868 |
| Cambodia ceded to France, 1867 | |
| Chulalongkorn, Rama V | 1868-1910 |
| Laos east of Mekong ceded to France, 1893; Laos west of Mekong ceded to France, 1904; Malay States ceded to Britain, 1909 |
|
| Vajravudh, Rama VI | 1910-1925 |
| Prajadhipok | 1925-1935, d.1941 |
| Military takes over, 1932 | |
| Ananda Mahidol | 1935-1946; in exile, except 1938 & 1946 |
| Siam becomes Thailand, 1939; Japanese Invasion, reluctant alliance, 1941-1945 |
|
| Bhumibol Adulyadej | 1946-present |
These lists are from Thailand, A Short History, by David K. Wyatt [Yale University Press, 1984, pp. 309-313]. A descripiton of the Thai language and its alphabet is in The World’s Major Languages, edited by Bernard Comrie [Oxford University Press, 1987, pp.757-775].