Formed March 15, 1915 (37th county)
Gem County (19,126), Emmett (7,663)
The Art Deco masonry courthouse of Gem County is located on Main Street at McKinley Street. Idaho State Highway 52 is three blocks to the west. It was built in 1939 through the Public Works Administration using the designs of Frank Hummel. An Army tank sits on the courthouse grounds. The county was created on March 15, 1915 as the 37th county and named for the Idaho State Nickname, Gem State. Emmett has always been the county seat. The county seat is named for the son of the postmaster Thomas Cahalan. Gem County was the birthplace of 1 Idaho Governor, Brad J. Little.
Gem County government consists of a sheriff, a prosecuter, a coroner, a clerk, a treasurer, and an assessor (executive). It has 3 Commissioners (legislative.) Six Circuit Court Judges and a Magistrate Court Judge serve Gem, Adams, Canyon, Owyhee, Payette, and Washington counties (judicial.) Gem County is in southwest Idaho directly northwest of Boise, Idaho. The Payette River flows through the county. The county center is 20.5 miles Northeast of Emmett nearer Ola. The county is surrounded clockwise by Adams, Valley, Boise, Ada, Canyon, Payette, and Washington counties.
The area of the county is 563 square miles. It is 40 out of 44 in the state. It ranks 19 out of 44 in population in the state. It has a density of 34.0 persons per square mile making it 12 out of 44 in the state. Gem County has 40.1% of its population in its incorporated areas. There are no Interstates or United States Highways in the county. The county is shaped like a peace pipe. Emmett is located in the southern quarter of the county near the border and is the only incorporated city. Emmett is the county seat and the largest city. It is 40.1% of the county population. This county is in the Boise City-Nampa Metropolitan Statistical Area.
Emmett
