| County: | Ziebach County |
| State: | South Dakota |
| Ex Image: | Ziebach County Courthouse.jpg |
| Ex Image Size: | 250px |
| Ex Image Cap: | Ziebach County Courthouse |
| Founded Year: | 1911 |
| Seat Wl: | Dupree |
| Largest City Wl: | Dupree |
| Area Total Sq Mi: | 1971 |
| Area Land Sq Mi: | 1961 |
| Area Water Sq Mi: | 9.3 |
| Area Percentage: | 0.5 |
| Population As Of: | 2020 |
| Population Total: | 2413 |
| Pop Est As Of: | 2023 |
| Population Est: | 2322 |
| Population Density Sq Mi: | auto |
| Time Zone: | Mountain |
| District: | At-large |
Ziebach County is a county in the U.S. state of South Dakota. As of the 2020 census, the population was 2,413.[1] Its county seat is Dupree.[2] It is the last county (or county equivalent) in the United States alphabetically.
The county's per-capita income makes it the fourth-poorest county in the United States.[3]
A county named Ziebach was created in Dakota Territory in 1877. However, after South Dakota became a state, this county was dissolved in 1898 and its areas absorbed by Pennington and Stanley counties. The present Ziebach County was created by the SD Legislature on February 1, 1911, and was fully organized by April 22.[4] The 1911 Ziebach County encompassed parts of the former counties of Schnasse, Armstrong and Sterling, which were the last three extinct counties of South Dakota to cease to exist. It was named for Frank M. Ziebach, a political figure in the Dakota Territory during the territorial period from 1861 to 1889. Previously the area had been used by trappers and in 1907 part was briefly a reservation for Ute Indians displaced from Utah and Wyoming. Early in the 20th Century cattle were raised in substantial numbers, but when the railroad bypassed the area this industry declined. Limited homesteading also occurred on the more fertile lands.[5]
The Cheyenne River flows east-northeastward along the southern boundary of Ziebach County. The Moreau River flows eastward through the upper portion of the county, and Cherry Creek flows southeastward through the lower portion, draining the area into the Cheyenne River. The terrain is composed of semi-arid rolling hills interrupted by buttes and carved by drainages and gullies, partly devoted to agriculture and cattle.[6] The terrain slopes to the south and the east; its highest point (except for the isolated Thunder Butte, at 2,733') is near its NW corner at 2582feet ASL.[7] The county has a total area of, of which is land and (0.5%) is water.[8] Almost the entire county lies within the Cheyenne River Indian Reservation. The balance of the county, along its extreme northern county line, lies within the Standing Rock Indian Reservation. It is one of five South Dakota counties that are composed entirely of land that is within the boundaries of Indian reservations.[9]
Ziebach County is part of the Great Plains and is characterized by rolling grasslands and numerous buttes. The buttes form the highest points of elevation in Ziebach County:
As of the 2020 census, there were 2,413 people, 732 households, and 528 families in the county.[11] The population density was . There were 882 housing units.
As of the 2010 census, there were 2,801 people, 836 households, and 638 families in the county. The population density was . There were 987 housing units at an average density of . The racial makeup of the county was 74.9% American Indian, 21.8% white, 0.2% black or African American, 0.1% Asian, 0.1% from other races, and 3.0% from two or more races. Those of Hispanic or Latino origin made up 3.1% of the population.
Of the 836 households, 53.7% had children under the age of 18 living with them, 39.0% were married couples living together, 29.3% had a female householder with no husband present, 23.7% were non-families, and 20.9% of all households were made up of individuals. The average household size was 3.35 and the average family size was 3.82. The median age was 25.4 years.
The median income for a household in the county was $27,578 and the median income for a family was $22,857. Males had a median income of $28,954 versus $24,327 for females. The per capita income for the county was $11,069. About 41.9% of families and 46.0% of the population were below the poverty line, including 56.1% of those under age 18 and 22.9% of those age 65 or over.
Ziebach County government does not include subdivision into townships. The county is divided into three areas of unorganized territory: Dupree, North Ziebach, and South Ziebach.
Ziebach County has traditionally been a swing county. Only Ronald Reagan in 1980 and Barack Obama in 2008 have topped sixty percent for either major party in the past six decades. Donald Trump won 48% of the vote in 2016, being the county or equivalent he won with the highest percentage of Native Americans. Joe Biden won 53% of the vote in 2020.