Most Thai Americans are the product of the revised regulations under the Immigration and Nationality Act of 1965 and the U.S. presence in Vietnam. Unlike other Southeast Asians, however, they came to the United States not as refugees but as professionals and spouses of members of the U.S. military. According to the U.S. census of 2000, 150,283 Americans claimed Thai descent. Only 6,965 Canadians reported Thai ancestry in the census of 2001. The greatest concentration of Thais in the United States is in California, particularly in southern California, but they are spread widely throughout the country wherever there are large military bases associated with the former American involvement in Southeast Asia. The majority of the small Thai community in Canada lives in Toronto and Vancouver. Thailand occupies 197,400 square miles on the Indochina and Malay Peninsulas in Southeast Asia. In 2002, the population was estimated at 61,797,751. The major ethnic groups in the country are Thais (75 percent) and Chinese (14 percent). Around 95 percent of the people are Buddhist and about 4 percent Muslim. Thais began migrating from southern China during the 11th century, conquering the native inhabitants and establishing a number of Thai kingdoms. In 1350, these were united in the Kingdom of Ayutthaya. Throughout much of its history, the Thai kingdom waged war with the kings of Burma and Cambodia for supremacy in the region. After 1851, Thailand became officially known as Siam, and its kings developed good relations with the British and French. Though Siam lost some territory to both European powers, it proved to be the only Southeast Asian country capable of resisting colonization. During the 1930s, the Thais developed a constitutional monarchy, leading the government to rename the country Thailand. After occupation by Japan during World War II (1939–45), Thailand fell largely into the hands of military leaders, who closely allied themselves to the United States in its cold war conflict in Vietnam, allowing U.S. bases to be established there. Thailand also became home to hundreds of thousands of Cambodians fleeing the Pol Pot regime after 1979. A steep downturn in the economy forced Thailand to seek more than $15 billion in emergency international loans in August 1997, and a new constitution won legislative approval on September 27. There was virtually no Thai immigration to the United States prior to the 1960s. With America’s growing presence there during the Vietnam War (1964–75), however, Thai doctors, nurses, and other professionals learned that the new Immigration and Nationality Act gave preference to skilled professionals, and a significant number chose to immigrate. Many U.S. servicemen married Thai women while stationed in Vietnam and brought them back to the United States after the war ended. By the late 1970s, some 5,000 Thais were in the United States, about three-quarters of them women. Many of the others were professionals or students. Thai immigration remained steady at an average of about 6,500 per year during the 1980s and early 1990s, but declined to less than 3,000 per year between 1997 and 2002, in part because a large percentage of Thai families had already been reunited. Except for students, spouses, and a small number of professionals, there has been almost no Thai immigration to Canada. Thailand has been politically stable for many years, and Thais do not have a long tradition of migration. Of 8,130 Thai immigrants in Canada in 2001, only 50 came before 1971, and 2,930 between 1991 and 2001.