The Lao originated in southern China and moved southward into present-day Laos, forming a kingdom in the Mekong River valley in the fourteenth century and pushing the earlier inhabitants of the area, the Kammu, into more mountainous areas. After three centuries, however, disputes over succession to the throne and foreign invasions split the country into three rival kingdoms in the north, center, and south. Caught between the growing power of the Siamese and the Vietnamese, the Lao lost power and territory so that today most Lao people live in Thailand (formerly Siam).
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