With 198,115 square miles and a population of more than 52 million, Thailand is drained by the Menam River Valley, and has a southern arm stretching down the Malay Peninsula. Eastern Thailand is drained by the Mekong River, which is the boundary between much of Thailand and Laos. Initially, Thailand was a buffer state between British interests in Burma and French interests in Indochina. Although 94 percent of the Thais are Buddhist, including the four million ethnic Chinese, the Malay minority along the southern extension are Moslem.

More than 60 percent of Thailand is forested, particularly the northern and eastern regions. From these forests come such valuable woods as teak, ebony, boxwood, and rosewood. Traditional agricultural is handicapped by elevation, slope, soil leaching, and winter drought. The chief breadbasket of Thailand is along the Menam River Valley. The central alluvial plains of the Menam are capable of producing two crops a year of rice, tobacco, and peanuts. Rice cultivation is found on 90 percent of the farmland and is the major export. Unlike most Asian nations, Thailand produces a rice surplus each year. The Thais usually supplement their diet with fish. Located in the delta on the lower Chao Phraya, Bangkok has a population of 2.4 million and is the commercial, financial, and political center of the country.

During the war in Vietnam, Thailand was a close American ally. Although the Thais had customarily gotten along with the Vietnamese, they were dubious of Communist intentions, feared the fall of Cambodia and Laos to guerrillas, and wanted above all else to safeguard their independence. By 1969, the Thais had a total of nearly 12,000 combat troops in Vietnam, including the elite Queen's Cobras and the Black Panther Division of the Royal Thai Army Volunteer Force. The United States 46th Special Forces Company assisted Thai forces in resisting Communist guerrilla activity along the Laotian border and in the south on the Malay Peninsula. The last of the Thai troops left Vietnam in April 1972.

The United States also had a formidable military presence in Thailand, including the 8th, 355th, 366th, and 388th Tactical Fighter Wings and the 307th Strategic Wing. Strategic bombing operations over North and South Vietnam frequently originated in Thailand.