The homestead act, the mass killing of buffalo, and the completion of the transcontinental railroad are most closely associated with the decline of the

Plains Indians

The Plains Indians are a Native American group who has traditionally lived in the Great Plains and the Canadian Prairies. Some well-known tribes are the Cheyenne, Comanche, Lakota, Kiowa and Apache.

These groups were nomadic or semi-sedentary, and their movement patterns generally followed those of the buffalo. Their reliance on buffalo was huge, as they obtained most of their clothing and food from them. The American government encouraged the extermination of buffalo in the 19th century as a strategy to control the Plains Indians and force them into reservations.

The Homestead Act was a system of land grant passed in May 1862. It allowed any American, including freed slaves, to claim up to 160 free acres of federal land. These grants were combined with the construction of the first transcontinental railroad (1893-69). Both events greatly altered the territory of the Plains Indians, forcing them to relocate.

affirmative action refers to the policies that take gender, race, or ethnicity into account in order to promote equal opportunity.

employers subject to title vii are prohibited from taking race or sex into account in any employment decisions. aa is a penalty for having any job group substantially statistically "underutilized" in any race or either sex. the employer must take steps to eliminate the underutilization, then stop, ending its aa efforts

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