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In page Custer, South Dakota:

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For thousands of years, the Black Hills had been part of the territory of varying tribes of indigenous peoples. They were within historical territory of the Oglala Sioux at the time of United States encounter, and within the Great Sioux Reservation established by the US Treaty of Fort Laramie (1868). Having established dominance in the area by the eighteenth century, the Oglala Sioux had long considered the Black Hills as sacred land.[citation needed]