kids encyclopedia robot

Nez Perce County, Idaho facts for kids

Kids Encyclopedia Facts
Quick facts for kids
Nez Perce County
St. Stanislaus Catholic Church in Lewiston.
Official seal of Nez Perce County
Map of Idaho highlighting Nez Perce County
Location within the U.S. state of Idaho
Map of the United States highlighting Idaho
Idaho's location within the U.S.
Country  United States
State  Idaho
Founded February 4, 1864
Named for Nez Percé tribe
Seat Lewiston
Largest city Lewiston
 • Total 856 sq mi (2,220 km2)
 • Land 848 sq mi (2,200 km2)
 • Water 8.2 sq mi (21 km2)  0.85%
 • Total 42,090
 • Density 49.17/sq mi (18.985/km2)
Time zone UTC−8 (Pacific)
 • Summer (DST) UTC−7 (PDT)
Congressional district 1st

Nez Perce County (pron. Nezz Purse) is a county located in the U.S. state of Idaho. As of the 2020 census, the population was 42,090. The county seat is Lewiston. The county is named after the Native American Nez Percé tribe. Nez Perce County is part of the Lewiston, IdahoWA Metropolitan Statistical Area.


Nez Perce County was originally organized in 1861, when the area was part of Washington Territory. It was reorganized in 1864 by the Idaho Territorial Legislature and was later subdivided into new counties. Rapid migration to the Palouse in the 1880s led to the formation of Latah County in 1888. Isolated from its county seat of Wallace in the Silver Valley, the southern portion of Shoshone County was annexed by Nez Perce County in 1904, then became Clearwater County in 1911. Lewis County was also formed from Nez Perce County in 1911.


According to the U.S. Census Bureau, the county has a total area of 856 square miles (2,220 km2), of which 848 square miles (2,200 km2) is land and 8.2 square miles (21 km2) (1.0%) is water.

Nez Perce County has two rivers, the Clearwater and the Snake, which meet in Lewiston and then flow west. The Clearwater flows from the east and the Snake from the south, creating the state border with Washington (and further upstream, Oregon). The lowest point in the state of Idaho is located on the Snake River in Lewiston in Nez Perce County, where it flows out of Idaho and into Washington. North of Lewiston, Idaho's western border is a political line.

The northern portion of the county is part of the Palouse, a wide and rolling agricultural region of the middle Columbia basin.

Adjacent counties

Nez Perce County map

Major highways

  • US 12.svg US-12
  • US 95.svg US-95
  • US 195.svg US-195
  • ID-3.svg SH-3

National protected areas


Historical population
Census Pop.
1870 1,607
1880 3,965 146.7%
1890 2,847 −28.2%
1900 13,748 382.9%
1910 24,860 80.8%
1920 15,253 −38.6%
1930 17,591 15.3%
1940 18,873 7.3%
1950 22,568 19.6%
1960 27,066 19.9%
1970 30,276 11.9%
1980 33,220 9.7%
1990 33,754 1.6%
2000 37,410 10.8%
2010 39,265 5.0%
2020 42,090 7.2%
U.S. Decennial Census
1790-1960 1900-1990
1990-2000 2010-2020 2020

2010 census

As of the 2010 United States Census, there were 39,265 people, 16,241 households, and 10,331 families living in the county. The population density was 46.3 inhabitants per square mile (17.9/km2). There were 17,438 housing units at an average density of 20.6 per square mile (8.0/km2). The racial makeup of the county was 90.1% white, 5.6% American Indian, 0.7% Asian, 0.3% black or African American, 0.1% Pacific islander, 0.7% from other races, and 2.5% from two or more races. Those of Hispanic or Latino origin made up 2.8% of the population. In terms of ancestry, 30.6% were German, 14.5% were Irish, 13.5% were English, and 7.7% were American.

Of the 16,241 households, 28.1% had children under the age of 18 living with them, 48.8% were married couples living together, 10.3% had a female householder with no husband present, 36.4% were non-families, and 28.6% of all households were made up of individuals. The average household size was 2.36 and the average family size was 2.88. The median age was 40.8 years.

The median income for a household in the county was $44,395 and the median income for a family was $55,180. Males had a median income of $42,451 versus $31,920 for females. The per capita income for the county was $23,899. About 8.5% of families and 11.6% of the population were below the poverty line, including 16.2% of those under age 18 and 5.9% of those age 65 or over.



Census-designated place

Unincorporated communities

kids search engine
Nez Perce County, Idaho Facts for Kids. Kiddle Encyclopedia.