Geographic Coordinates
- 15°00′N 100°00′E / 15°N 100°E / 15; 100
The fertile floodplain and tropical monsoon climate, ideally suited to wet-rice (tham na) cultivation, attracted settlers to this central area over to the marginal uplands and the highlands of the northern region or the Khorat Plateau to the northeast.
By the 11th century AD, a number of loosely connected rice-growing and trading states flourished in the upper Chao Phraya Valley. They broke free from domination of the Khmer Empire, but from the middle of the 14th century gradually came under the control of the Ayutthaya kingdom at the southern extremity of the floodplain.
Successive capitals, built at various points along the river, became centers of great Thai kingdoms based on rice cultivation and foreign commerce. Unlike the neighboring Khmer and Burmese, the Thai continued to look outward across the Gulf of Thailand and the Andaman Sea toward foreign ports of trade.
When European imperialism brought a new phase in Southeast Asian commerce in the late 1800s, Thailand (known then as Siam) was able to maintain its independence as a buffer zone between British-controlled Burma to the west and French-dominated Indochina to the east, but losing over 50% of its territory in the process. Fortunately, most of the areas lost contained a non-Thai population (Khmer, Lao or Shan). The Thai-speaking heartland remains intact.
Read more about this topic: Geography Of Thailand