Counties have played an important role in Idaho's governmental history. The Idaho constitution of 1890 directed the legislature to: establish a system of county government which shall be uniform throughout the state.

When Idaho became a territory in March, 1863, there were four counties in existence: Boise, Idaho, Nez Perce and Shoshone. By the time Idaho became a state 27 years later, there were 15 counties. The rest of the 44 counties came into existence during the 30 years after Idaho became a state. Two of the former counties disappeared during this time. Alturas, which was created in 1864, was later divided into the many counties now found in central Idaho. Logan County was only in existence for six years, from 1889 to 1895. It was combined with Alturas to form Blaine County and Lincoln County, which was formed just two weeks after Logan lost its identity.

The legislature has kept firm control of the taxing powers of the counties, giving them only the right to tax property. These property taxes, as they are called, are the main source of money for county operations.

As the cost of government has grown and government services at the county level have grown, the counties have come to rely more on money from other sources. Such aid has grown since the 1930s and the state and federal governments have taken over many county functions such as welfare. Counties share in highway revenues, inheritance taxes and taxes on such things as cigarettes, liquor and gasoline.

The boards of county commissioners are the administrators of the counties and are given by law the responsibility of supervising the conduct of all county officers. Within the counties are many elected officials who are responsible for the many different duties necessary to keep the county running smoothly. The county clerk, the sheriff, assessor, treasurer, prosecuting attorney and coroner all have important jobs to do for the county.

The clerk is the person who records all of the licenses and records of property ownership. It is also the clerk's job to be sure that all records are kept accurately. The sheriff makes sure that the laws of the nation, the state and the county are obeyed throughout the county. The assessor decides how much tax people should pay on their property. The treasurer keeps track of the county's money and often acts as a tax collector, also. The prosecuting attorney represents the county in court. The coroner investigates unusual deaths. The coroner may also hold a trial or inquest if he suspects that a crime has been committed.

County governments are more important to people living in areas that have no large cities. Areas away from cities are called rural areas. Most of Idaho is rural. There are some urban, or city, areas. In these areas the county and city officials work together to make decisions that are best for everyone in the area.