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The indigenous peoples of the Americas are the pre-Columbian peoples of the Americas and their descendants. Although some indigenous peoples of the Americas were traditionally hunter-gatherers--and many, especially in the Amazon basin, still are--many groups practiced aquaculture and agriculture. The impact of their agricultural endowment to the world is a testament to their time and work in reshaping and cultivating the flora indigenous to the Americas. Although some societies depended heavily on agriculture, others practiced a mix of farming, hunting and gathering.
Guatemala has one of the largest Indigenous populations in Central America, with approximately 39.3% of the population considering themselves Indigenous. The Indigenous demographic portion of Guatemala's population consists of majority Mayan groups and one Non-Mayan group. The Mayan portion, can be broken down into 23 groups namely K'iche 11.3%, Kaqchikel 7.4%, Mam 5.5%, Q'eqchi' 7.6% and Other 7.5%. The Non-Mayan group consists of the Xinca who are another set of Indigenous people making up 0.5% of the population. The Mayan tribes cover a vast geographic area throughout Central America and expanding beyond Guatemala into other countries. One could find vast groups of Mayan people in Boca Costa, in the Southern portions of Guatemala, as well as the Western Highlands living together in close communities. Within these communities and outside of them, around 23 Indigenous languages or Amerindian Languages are spoken as a first language. Of these 23 languages, they only received official recognition by the Government in 2003 under the Law of National Languages. The Law on National Languages recognizes 23 Indigenous languages including Xinca, enforcing that public and government institutions not only translate but also provide services in said languages. It would provide services in Cakchiquel, Garifuna, Kekchi, Mam, Quiche and Xinca. The Law of National Languages has been an effort to grant and protect Indigenous people rights not afforded to them previously. Along with the Law of National Languages passed in 2003, in 1996 the Guatemalan Constitutional Court had ratified the ILO Convention 169 on Indigenous and Tribal Peoples. The ILO Convention 169 on Indigenous and Tribal Peoples, is also known as Convention 169 . Which is the only International Law regarding Indigenous peoples that Independent countries can adopt. The Convention, establishes that Governments like Guatemala's must consult with Indigenous groups prior to any projects occurring on tribal lands.

How long have the tribes been there?

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The Khmer Krom (Khmer: khmaerkroom, Vietnamese: Kho Me Crom) are ethnically Khmer people living in the south western part of Vietnam, where they are recognized as one of Vietnam's fifty-three ethnic minorities. In the Khmer language, Krom means "lower" or "below", as it refers to an area of 89,000 square kilometres (34,363 sq mi) around modern day Saigon and the Mekong Delta, which used to be the southeasternmost territory of the Khmer Empire until its incorporation into Vietnam under the Nguyen lords in the early 18th century. This marks the final stage of the Vietnamese "March to the South" (nam tien).
Khmer nationalist Son Ngoc Thanh (1908-77) was a Khmer krom, born in Tra Vinh, Vietnam. Thanh was active in the independence movement for Cambodia. With Japanese support he became the prime minister of Cambodia in March 1945 but was then quickly ousted with the return of the French later that year. Widely supported by the Khmer Krom during the First Indochina War, Thanh's role faded in Vietnam after 1954 as he became more embroiled with politics in Cambodia proper, forming an opposition movement against Prince Sihanouk. During the Vietnam War and direct American involvement between 1964 and 1974, the Khmer Krom were recruited by the United States Armed Forces to serve in MIKE Force. The force fought on the side of South Vietnam against the Viet Cong but in time the militia regrouped as the "Front for the Struggle of Kampuchea Krom" (French: Front de Lutte du Kampuchea Krom). Headed by a Khmer Krom Buddhist monk, Samouk Sen, the group was nicknamed the "White Scarves" (Khmer: Kangsaing Sar; Vietnamese: Can Sen So) and allied itself with FULRO against South Vietnam. FULRO was an alliance of Khmer Krom, Montagnard, and Cham groups. The anti-Communist prime minister of the Khmer Republic (1970 - 1975) Lon Nol planned to recapture the Mekong Delta from South Vietnam. After the Fall of Saigon in 1975 and the Communist take-over of all of Vietnam, the Kampuchea Krom militia found itself embattled with People's Army of Vietnam. Many of the fighters fled to Khmer Rouge-controlled Democratic Kampuchea hoping to find a safe haven to launch their operations inside Vietnam. The "White Scarves" arrived in Kiri Vong District in 1976, making overture to the Khmer Rouge and appealing to the leader Khieu Samphan directly for assistance. The force was disarmed and welcomed initially. Subsequent orders from the Khmer Rouge leadership however had Samouk Sen arrested, taken to Phnom Penh, tortured, and killed. His force of 67 Khmer Krom fighters were all massacred. During the following months, some 2,000 "White Scarves" fighters crossing into Kampuchea were systematically killed by the Khmer Rouge. In the late 1970s, the Kampuchean Revolutionary Army attacked Vietnam in an attempt to reconquer the areas which were formerly part of the Khmer Empire, but this military adventure was a total disaster and precipitated the invasion of Democratic Kampuchea by the People's Army of Vietnam and subsequent downfall of the Khmer Rouge, with Vietnam occupying Kampuchea.

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Subsequent orders from the Khmer Rouge leadership however had Samouk Sen arrested, taken to Phnom Penh, tortured, and killed.