Campbell County is named for John Allen Campbell, who was the first Governor of the Wyoming Territory.
Surrounding County Courthouses:
N – Powder River County, Montana
E – Crook County and Weston County
S – Converse County
W – Johnson County and Sheridan County
Created: February 13, 1911 
County Seat:
Gillette 1911 – present
County Courthouse – Gillette
Location: 500 Gillette Avenue / West 5th Street
Built: 1970 – 1971
Style: Modern
Architect: Henry Therkildsen
Contractor: Spiegelberg Lumber & Building Company
Description: The building faces east and is a two story red-brown colored brick, stone and concrete structure. The building is located on landscaped grounds in the center of Gillette. The east building has a raised basement as the first story. The east front has a central entrance on the second story which projects from the main building and has flagstone vertical sections on each side of the entrance. There are white colored concrete blocks around the windows. The roof line is flat. In the interior is an entrance lobby. To the north are the three County District Court courtrooms and to the south are the three County Circuit Court courtrooms. The building houses the County District Court and County Circuit Court of the 6th Judicial District. The North Addition was constructed in 1980 to 1982. The building was remodeled in 1986 adding courtrooms A and B. In 2004 to 2005, the Vault Addition on the south side was constructed. The architect was Schultz Foss Architects and the contractor was Van Ewing Construction Inc.
See: The architect, Henry Therkildsen also designed the courthouse in Converse County.
See: The 6th Judicial District includes Crook County and Weston County.
History: The county was created in 1911 and Gillette was selected as the county seat. The first courthouse was a small one story frame structure located at 4th Street and Kendrick Avenue. In 1924, the county purchased the two story brick house owned by John T Daly and his wife located at Gillette Avenue and 5th Street. The second courthouse was converted for use as a courthouse. The architect was Randall & Jorday and the contractor was N A Pearson. A reinforced concrete addition with courtroom on the second story was constructed. The third and present courthouse was constructed in 1970 to 1971 at a cost of $900,000. The cost of the 1980 to 1982 addition was $1,800,000 and the 2004 to 2005 addition was $10,700,000.
County Courthouse - Gillette
County District Court courtroom
County District Court courtroom
Photos taken 2009 and 2023