Why was "Thailand Never Colonized Any Country" ??

Royal Thai is a place situated several different
geographical areas. To the north, the situation
is mountainous, and its highest point is Doi
Inthanon (2576 m). Northeast of Khorat Overlay, which bordered on the east by the Mekong river. Central region of the state-dominated Chao Phraya river valley that is almost entirely flat, and flows into the Gulf of Thailand. To the south there is a wide Isthmus of Kra to the Malay Peninsula.

The local climate is tropical and characterized
by monsoons. There are monsoon rains, warm
and cloudy from the southwest between mid
May and September, as well as a dry and cool monsoon from the northeast from November to mid March. Isthmus to the south is always hot and humid. Major cities in addition to the capital Bangkok include Nakhon Ratchasima, Nakhon Sawan, Chiang Mai, and Songkhla.

Royal Thai borders with Laos and Myanmar in
the north, with Malaysia and the Gulf of Siam in the south, with Myanmar and the East Sea in the west and with Laos and Cambodia to the east. Its geographical coordinates are 5 ° -21 ° N and 97 ° -106 ° East

Internal factors,
The King of Thailand at that time are open to the outside world. Already there are educated people in Thailand at that time was primarily a family-friendly of Kingdom. King's son, the royal family being sent abroad (to Europe) in order to seek knowledge, even bring in teachers from Europe to the kingdom to teach science

External factors,
The State of Thailand at that time became a buffer state (border) regions of the European colonialists, the British in the north and south, the French in Indochina and the Dutch in the Indies