Select Page

History and Facts of Wyoming Counties

Wyoming Counties – There were originally five counties in the Wyoming Territory: Laramie and Carter, established in 1867; Carbon and Albany established in 1868; and Uinta, an annexed portion of Utah and Idaho, extending from Montana (including Yellowstone Park) to the Wyoming-Utah boundary. 

Today’s Wyoming counties did not always exist in the present form. They went through many different changes in the space of a few short years. In the beginning Wyoming Territory had 5 counties. They were Carbon, Carter, Laramie and Albany, which were originally part of Dakota Territory, and Green County, which was originally part of Utah.

On May 19, 1869, the newly-organized territory added  Uinita County  County from portions of Idaho and Utah that were previously unorganized. At that same time, Carter County became Sweetwater County.

The Territory of Wyoming, originally was part of Dakota Territory, was organized on July 25, 1868 and existed until July 10, 1890. Cheyenne was the territorial capital.

The State of  Wyoming was admitted to the Union as a the 44th state on July 10, 1890 with 13 counties. Wyoming now has 23 Counties., which were all in existence by 1923.

In 1867 the first Wyoming counties were formed. The first 2 counties created were Sweetwater County and Laramie County. The last county to be formed was Teton County on February 15, 1921.

States bordering Wyoming are ColoradoMontanaNebraska, South DakotaUtah and Idaho.

List of Wyoming Counties

Wyoming is divided into 23 counties.

List of Old Former / Extinct Wyoming Counties

Wyoming has 3 counties that no longer are in existence. These counties were established and renamed in the 19th century; county borders have modified very little since 1900 in Wyoming.

The below Wyoming counties no longer exist:

Carter County, Wyoming

Created on December 27, 1867 as a county within the Dakota Territory. It was formed from part of  Laramie County and named in honor of Judge W.A. Carter of Fort Bridger. It was renamed to Sweetwater County on December 13, 1869.

Hanover County County, Wyoming

Created on February 14, 1911 as a county within the Dakota Territory. It was formed from part of  Laramie County and named in honor of Judge W.A. Carter of Fort Bridger.

It was renamed to Washakie County on February 14, 1911 and named in honor of was named for the head chief of the Shoshone people, Chief Washakie.

Pease County, Wyoming

Created on December 8, 1875. It was formed from parts of Albany, Carbon, and Sweetwater Counties and was named for Dr. E. L. Pease of Uinta County.

Pease County was renamed to Johnson County on December 13, 1879 in honor of for E. P. Johnson, a Cheyenne attorney.

Map of Wyoming County Boundary Changes from 1848 to 1965

This Interactive Map of Wyoming Counties show the historical boundaries, names, organization, and attachments of every county, extinct county and unsuccessful county proposal from the creation of Wyoming from 1848-1965.

Fun Facts about Wyoming Counties

County Name Facts

The County names:

  • 0 of them named for Native American words or people,

Counties by Year

  • Laramie County was the first county created on January 9, 1867.
  •  The last counties to be formed were Sublette County on February 15, 1921 (organized in 1923) and Teton County on February 15, 1921 (organized in 1922).

Facts for County Size

Facts for County Population (2017 Est.)

Facts for Wyoming Counties and Cities

Wyoming’s 10 largest cities (2019) are:

  1. Cheyenne (65,864) is in Laramie County
  2. Casper (59,171) is in Natrona County
  3. Gillette (31,783) is in Campbell County
  4. Laramie (32,715) is in Albany County
  5. Rock Springs (23,014) is in Sweetwater County
  6. Sheridan (18,071) is in Sheridan County
  7. Green River (11,777) is in Sweetwater County
  8. Evanston (11,967) is in Uinta County
  9. Riverton (11,003) is in Fremont County
  10. Jackson (10,413) is in Teton County