The Pine Ridge Indian Reservation (Wazí Aháŋhaŋ Oyáŋke in Lakota

Lakota language

Lakota is a Siouan language spoken by the Lakota people of the Sioux tribes. While generally taught and considered by speakers as a separate language, Lakota is mutually understandable with the other two languages , and is considered by most linguists one of the three major varieties of the Sioux...

, also called Pine Ridge Agency) is an Oglala Sioux Native American

Native Americans in the United States

Native Americans in the United States are the indigenous peoples in North America within the boundaries of the present-day continental United States, parts of Alaska, and the island state of Hawaii. They are composed of numerous, distinct tribes, states, and ethnic groups, many of which survive as...

 reservation

Indian reservation

An American Indian reservation is an area of land managed by a Native American tribe under the United States Department of the Interior's Bureau of Indian Affairs...

 located in the U.S. state

U.S. state

A U.S. state is any one of the 50 federated states of the United States of America that share sovereignty with the federal government. Because of this shared sovereignty, an American is a citizen both of the federal entity and of his or her state of domicile. Four states use the official title of...

 of South Dakota

South Dakota

South Dakota is a state located in the Midwestern region of the United States. It is named after the Lakota and Dakota Sioux American Indian tribes. Once a part of Dakota Territory, South Dakota became a state on November 2, 1889. The state has an area of and an estimated population of just over...

. Originally included within the territory of the Great Sioux Reservation

Great Sioux reservation

The Great Sioux Reservation was established in the Fort Laramie Treaty of 1868, and includes all of modern western South Dakota and modern Boyd County, Nebraska...

, Pine Ridge was established in 1889 in the southwest corner of South Dakota on the Nebraska border. Today it consists of 3,468.86 sq mi (8,984.306 km²) of land area and is the eighth-largest reservation in the United States, larger than Delaware

Delaware

Delaware is a U.S. state located on the Atlantic Coast in the Mid-Atlantic region of the United States. It is bordered to the south and west by Maryland, and to the north by Pennsylvania...

 and Rhode Island

Rhode Island

The state of Rhode Island and Providence Plantations, more commonly referred to as Rhode Island , is a state in the New England region of the United States. It is the smallest U.S. state by area...

 combined.

The reservation encompasses the entirety of Shannon County

Shannon County, South Dakota

As of the census of 2000, there were 12,466 people, 2,785 households, and 2,353 families residing in the county. The population density was 6 people per square mile . There were 3,123 housing units at an average density of 2 per square mile...

, the southern half of Jackson County

Jackson County, South Dakota

As of the census of 2000, there were 2,930 people, 945 households, and 675 families residing in the county. The population density was 2 people per square mile . There were 1,173 housing units at an average density of 1 per square mile...

 and the northwest portion of Bennett County

Bennett County, South Dakota

As of the 2010 census there were 3,431 people in Bennett County, in 1,090 households . The racial and ethnic composition of the population was 33.3% non-Hispanic white, 0.1% black or African American, 60.4% non-Hispanic Native American, 1.1% Hispanic Native American, 0.4% Asian, 0.1% Pacific...

.