Fitness Wellness ↔ relates to ↔ Agriculture

The Treasure Valley is a valley in the western United States, primarily in southwestern Idaho, where the Payette, Boise, Weiser, Malheur, and Owyhee rivers drain into the Snake River. It includes all the lowland areas from Vale in rural eastern Oregon to Boise, and is the most populated area in Idaho. Historically, the valley had been known as the Lower Snake River Valley or the Boise River Valley. Pete Olesen, president of the valley's association of local Chambers of Commerce, coined the name "Treasure Valley" in 1959 to reflect the treasure chest of resources and opportunities that the region offered. The valley has a very diverse terrain, from sage flatlands, to mesas, agricultural areas, and urbanized areas.

eflect the treasure chest of resources and opportunities that the region offered. The valley has a very diverse terrain, from sage flatlands, to mesas, agricultural areas, and urbanized areas. As the Boise Metropolitan Area grows, more and more undeveloped and agricultural land is being urbanized. History Settling the region The tribes that roamed the area, specifically, were the Northern Paiute and Shoshone. In 1834, Thomas McKay built the original Fort Boise, in the area near present-day Parma, which was run for a time by Francois Payette. It later was moved because of flooding troubles and was abandoned in 1854. The Oregon Trail runs through the Treasure Valley. The valley was settled for the most part by ranchers and farmers, initially to supply the gold and silver mining communities in the higher elevations nearby: Idaho City in the Boise Basin and Silver City in the Owyhees. A new Fort Boise was constructed by the U.S. Army in 1863 in present-day Boise, from which the city grew.

icultural land is being urbanized. History Settling the region The tribes that roamed the area, specifically, were the Northern Paiute and Shoshone. In 1834, Thomas McKay built the original Fort Boise, in the area near present-day Parma, which was run for a time by Francois Payette. It later was moved because of flooding troubles and was abandoned in 1854. The Oregon Trail runs through the Treasure Valley. The valley was settled for the most part by ranchers and farmers, initially to supply the gold and silver mining communities in the higher elevations nearby: Idaho City in the Boise Basin and Silver City in the Owyhees. A new Fort Boise was constructed by the U.S. Army in 1863 in present-day Boise, from which the city grew.

Boise (locally also ) is the capital and most populous city in the U.S. state of Idaho. It is the county seat of Ada County. The population of the city was 235,685 at the 2020 census. The Boise metropolitan area, located in the Treasure Valley, includes five counties of Idaho with an estimated population of 846,000, the most populous metropolitan area in Idaho and 95th-most populous in the United States. Located on the Boise River in southwestern Idaho, it is 41 miles (66 km) east of the Oregon border and 110 miles (177 km) north of the Nevada border. Downtown Boise's elevation is 2,704 feet (824 m) above sea level. Boise is home to major employers in the technology, manufacturing, and service sectors, including companies such as Micron Technology and Hewlett-Packard.

an area in Idaho and 95th-most populous in the United States. Located on the Boise River in southwestern Idaho, it is 41 miles (66 km) east of the Oregon border and 110 miles (177 km) north of the Nevada border. Downtown Boise's elevation is 2,704 feet (824 m) above sea level. Boise is home to major employers in the technology, manufacturing, and service sectors, including companies such as Micron Technology and Hewlett-Packard.

...that the military should continue killing Indians 'until the last Indian in the Territories was either on his reservation or enriched the sagebrush with his decaying carcass.' ...if the Indians refused to move there, 'they will be killed or put on the reservation by force, and certainly shot if they don't stay there.' Furthermore, the editor continues, 'The idea that the Indians have any right to the soil is ridiculous. ...They have no more rights to the soil of the Territories of the United States than wolves or coyotes...' This would be our plan of establishing friendship upon an eternal basis with our Indians: Let all the hostile bands of Idaho Territory be called in (they will not be caught in any other manner) to attend a grand treaty; plenty of blankets and nice little trinkets distributed among them; plenty of grub on hand; have a real jolly time with them; then just before the big feast put strychnine in their meat and poison to death the last mother's son of them. At the same time, native warriors around the valley, under the leadership of Howluck also known as "Bigfoot" among white settlers, among others, waged an escalating and intensified guerrilla campaign of harassment of passerby caravans along the Oregon Trail. The United States Army also escalated and intensified "punitive expeditions" against formations of warriors and against civilian communities as well. This marked the start of the "unofficial" Snake War in 1866. This war lasted until 1868, and is statistically the deadliest of the Indian Wars in the West in terms of casualties. In the end, 1,762 men were counted as the casualties of this war from both sides. In 1868, Fort Hall Indian Reservation was established in Southeastern Idaho, about 220 miles upstream, according to the terms of Fort Bridger Treaty. The Boise Valley Shoshone and Bannock Tribes were not party to this treaty. Nevertheless, in April 1869, the United States Military embarked on a campaign of "Removal, rounding up of natives in the region including in and around Boise, and expelling them with cavalry escort to Fort Hall Indian Reservation. This period is known among the Shoshone and Bannock people as Idaho's Trail of Tears. Some of the natives managed to escape, and they ran to either Duck Valley or Fort McDermitt in Nevada. Incorporation and growth Boise's early growth was significantly driven by its role in supplying the nearby gold towns that sprung up in the 1860s northeast and then southwest of the town. Miners sometimes wintered in Boise and a number of early prominent businessmen were miners who settled in town in the years after the gold rush waned. By 1864 substantial agricultural production was underway on easily irrigated lands near the river and three canal companies had been incorporated. Early transportation improvements were largely a result of toll road franchises awarded by the territorial legislature starting in the 1860s. These first ran from Fort Boise to the mining centers in the Boise Basin and east to Rocky Bar and to Rattlesnake Station where they connected to the Oregon Trail. Territorial census records from a special 1864 enumeration list the population of Boise as 1,658, and an act of December 12, 1864, was the first attempt by the Idaho Territorial Legislature to incorporate the city. This was rejected by voters the following March. Two more unsuccessful attempts were made to organize a city administration by election before the 1866 version of the city charter was approved by voters on January 6, 1868. The growing number of homes and businesses, for which owners wanted proper legal title, may have contributed to the eventual success of incorporation. All of these rejected efforts to incorporate the city came after Boise had been controversially made the state capital in 1864 over strong opposition from northern Idaho interests. This decision reflected the rapid shift of population growth from north to south after the discovery of gold in southern Idaho. By 1868 Boise had over 400 permanent buildings with a wide range of commercial services. 1868 also marked the formal beginning of a long advocacy for railroad connections to other Idaho communities and, just as importantly, to other growing cities in the west such as Portland, Oregon. Competing railroad and western state government interests frustrated these efforts for many years. Designed by Alfred B. Mullett, the U.S. Assay Office at 210 Main Street was built in 1871 and today is a National Historic Landmark. It first began accepting gold and silver for purchase on March 2, 1872, largely eliminating the need to transport ore to the mint in San Francisco. A territorial penitentiary, now known as the Old Idaho State Penitentiary, opened the same month several miles east of town. Mining continued to be important to Boise's economic growth and periodic booms contributed to population growth as well, though production of gold and silver probably peaked in the 1860s. 1882's gold and silver production of $3,500,000 declined to $1,488,315 (including lead) by 1899. Boise began to earn its City of Trees nickname in this period with a popular focus on a range of tree planting projects. Thomas J. Davis planted several thousand fruit trees in 1864 and several other early businessmen either founded nurseries or orchards of their own. In the 1870s tree planting began in earnest in downtown Boise led by prominent hotels as well as businessmen and residents. In 1907 Davis donated 43 acres of his orchard property to the city for use as a park in the name of his wife Julia. Commercial agriculture continued to expand, but was slowed by the lack of reliable rail links to regional and national markets and by a lack of large scale irrigation projects, which themselves were often tied to hoped-for railroad projects for financing. A.D. Foote, a successful mining engineer, drew up plans to irrigate up to 500,000 acres immediately south of Boise in 1882, but progress was halting and smaller farms were the norm until after the turn of the century with most located near to the river bottom where soil was productive and irrigation more easily achieved. Fruit orchards proliferated and sugar beets, still an important agricultural industry in Idaho, began to be widely cultivated in the 1890s. Cattle and sheep farming became increasingly important as the century closed. With the exception of dairy, most livestock products were exported from Idaho, unlike other agricultural products which were still largely scaled to support local markets. The timber industry also increasingly thrived in the Boise market in the 1880s and 1890s. Large quantities of timber were exported from elsewhere in Idaho, but a growing Boise supported the expansion of Alexander Rossi's sawmill, first established in 1865. Prominent early Boisean William Ridenbaugh had inherited control of the canal now bearing his name from his uncle William Morris in 1878 and later partnered with Rossi to expand the sawmill capacity under the name Rossi and Ridenbaugh Lumber Company. Their materials supported bridge building and the rapid expansion of Boise in the 1890s. As with many early infrastructure ventures, electrification succeeded only after at least one false start. July 4, 1887, marked the start of electrical transmission from a plant located on the Bench. William Ridenbaugh provided expertise and manpower for the water supply and several months were spent rigging poles and lines from the Bench to the service area across the river. Additional electrical supplies allowed the building of an electric streetcar line in 1891. This ran without interruption until buses replaced the lines in 1927, tracking—and sometimes driving—the development of Boise and nearby communities. This system expanded over several decades, reaching into the North End, South Boise and across the river on Front St. A loop line, completed in 1912, ran as far as Caldwell and Nampa, providing transport throughout the valley. Three early trolley companies merged in 1912 to form the Idaho Traction Company with a depot at 7th and Bannock Streets downtown. Additional services and urban amenities arrived in the 1890s as Boise grew. Exploratory drilling for hot water was successful in 1890 and by the end of the decade many homes along Warm Springs avenue were being heated by this source. A natatorium was built in 1892 close to the source of the hot water near the Idaho State Penitentiary. Churches serving several denominations, a Jewish synagogue, a major hardware store and department store, a Masonic hall, the Columbia Theater, Saint Alphonsus' Hospital, a number of parochial and secular schools, a City Hall and a new Union Pacific passenger station, constructed when service was finally extended to downtown, were all built during the 1890s. Falk's Department Store sponsored a semi-professional baseball team representing Boise from at least 1892 and the city supported other organized sports as they became popular.

pa ( ) is the most populous city in Canyon County, Idaho, United States. The population was 100,200 at the 2020 census. It is Idaho's third-most populous city. Nampa is about 20 miles (32 km) west of Boise along Interstate 84, and 6 miles (9.7 km) west of Meridian. It is the second principal city of the Boise metropolitan area. The name "Nampa" may have come from a Shoshoni word meaning 'moccasin' or 'footprint'. According to toponymist William O. Bright, the name comes from the Shoshoni word /nampai/, meaning "foot".

History Nampa had its beginnings in the early 1880s when the Oregon Short Line Railroad built a line from Granger, Wyoming, to Huntington, Oregon, that passed through Nampa. In Nampa there is a history museum that marks the railroad's significance. More railroad lines sprang up through Nampa, making it an important railroad town. Alexander and Hannah Duffes established one of the town's first homesteads, eventually forming the Nampa Land and Improvement Company with the help of their friend and co-founder, James McGee. Despite the name, many early settlers called the town "New Jerusalem" because of its citizens' strong religious focus. After only a year the town grew from 15 homes to 50. As amenities were added, Nampa continued to grow, and it was incorporated in 1891. Downtown Nampa's street grid is oriented with the railroad tracks, which run northwest–southeast; this was done intentionally by Alexander Duffes to prevent accidents like one that occurred earlier in a town he had platted near Toronto, where a woman and her two children were killed by a train when their buggy wheel got stuck as they crossed the tracks. As the Oregon Short Line railroad originally bypassed Boise, Nampa has the fanciest of many railroad depots built in the area. Nampa gained attention in 1889 due to a purported archaeological discovery known as the Nampa figurine. George Frederick Wright wrote up details that year for the Boston Society of Natural History. The first elementary school was built in the 1890s. Lakeview School was on a hill on 6th Street and 12th Avenue North, with a view of Lake Ethel. Just after the school's centennial celebration, it was condemned as a school and sold to the First Mennonite Church. In 2008 the building was refurbished, and it is now used by the Idaho Arts Charter School. Lake Ethel, an irrigation reservoir, had long been the site of community picnics, and many citizens fished, swam, boated, and even hunted on it and its surrounding property. But the hunting didn't last long, as O. F. Persons, owner of the adjoining homestead, took offense when local hunters started shooting his pet ducks. The city later auctioned off the lake. E. H. Dewey (a former Nampa mayor) was the only bidder. But occasional flooding led to a series of lawsuits from neighbors. Dewey eventually drained Lake Ethel. Not long after, the city council became interested in buying back the Fritz Miller property as well as the Dewey home. Pressure had been building for more than four years. Nampa citizens wanted another park. On August 7, 1924, the city council passed an ordinance to purchase the Miller property and name it Lakeview Park. A bandstand was completed in 1928, and the municipal swimming pool opened on August 13, 1934. It is Nampa's largest park and many community celebrations are held there. Colonel William H. Dewey, a man who made a fortune mining in Silver City, built the Dewey Palace Hotel in 1902 for $250,000. He died in his hotel in 1903, leaving his son $1 million. The hotel survived the great fire of 1909, which burned several blocks of downtown Nampa, but was razed in 1963 after redevelopment plans failed. Relics from the hotel such as the chandelier and the hotel safe can be found at the Canyon County Historical Museum, which is in the old train depot on Front Street and Nampa City Hall. After demolition the location on First Street between 11th and 12th Ave. South was sold to private enterprise, including a bank and tire store, replacing this building with modern structures. A public-use postage stamp sized park was later placed across the street from the old palace property as a collaboration between the Downtown Alliance of Nampa (the local business council) and an Eagle Scout Project for the Boy Scouts of America. The park includes a large mural/wall sculpture of running horses commissioned for the project. A Carnegie library was built downtown in 1908; it burned down after the library moved in 1966. Nampa Public Library was then on the corner of 1st Street and 11th Avenue South in the old bank building. A new library, on 12th Avenue South, opened in 2015. Deer Flat Reservoir, an offstream irrigation storage reservoir, was constructed by the United States Bureau of Reclamation between 1906 and 1911. Known locally as Lake Lowell, it is surrounded by the Deer Flat National Wildlife Refuge, established in 1909 by President Theodore Roosevelt. The refuge is administered by the U.S. Fish and Wildlife Service. Lake Lowell is filled by the concrete New York Canal; the water is diverted from the Boise River a few miles below Lucky Peak Dam. In 1910, the Idaho State School and Hospital was built northwest of Nampa for the state's developmentally challenged population. It opened in 1918. The institution was largely self-sufficient, with a large farm staffed by the residents. The higher-functioning residents also cared for residents who could not care for themselves. The land for the farm was sold and is now golf courses (Centennial and Ridgecrest), and the residents no longer give primary care to other residents. The institution is modernized and remains in operation, though a few of the oldest buildings now house juvenile offenders. Nampa held an annual harvest festival and farmers' market from about 1908, a time of celebration and community fun. From this festival emerged the Snake River Stampede Rodeo in 1937, which continues to this day. It is one of the top 12 rodeos in the pro rodeo circuits. In 1913, a local congregation of the Church of the Nazarene built a small elementary school, which became to Northwest Nazarene College in 1915 and finally Northwest Nazarene University. As of 2025, the university has approximately 1,800 undergraduate and graduate students. Karcher Mall opened in 1965, the first enclosed shopping mall in the Treasure Valley. It was "the place to gather" for several decades until the Boise Towne Square mall was built in Boise in 1988, drawing business away. Karcher Mall was renamed District 208 in 2022. The Idaho Press-Tribune is the local newspaper for the Canyon County area.

W. J. McClelland, c.1901–1903 Frank H. Sutherland, c.1903–1904 H. A. Partridge, c.1904–1905, 1907–1908, 1913–1914 Rudolphus W. Purdum, c.1905–1906 E. H. Dewey, c.1909–1911 T. E. Munhall, c.1915–1917 Robert A. Davis, c.1917–1919 H. H. Keim, c.1919–1920 J. Fremont Bow, 1921–1923 Eugene Emerson, c.1923–1925 George Meffan, 1925–1929 Eustace Smallwood, c.1929–1930 E. W. Rising, c.1933–1935 George I. Van Name, 1935–1937 R. Lewis Ord, 1937–1939 Ben H. Waigand, 1939–1943 A. E. Lindsey, c.1943–1945 Sevren G. Honstead, 1945–1947 Peter Johnson, 1947–1951 Preston Capell, c.1951–1957 Thomas Leupp, 1957–1961 Ernest Starr, 1961–1981 Winston K. Goering, 1981–1993 Maxine Horn, c.2001 Tom Dale, c.2002–2013 Bob Henry, c.2014–2017 Debbie Kling, 2018–2025 Rick Hogaboam, 2026 Notes Geography According to the United States Census Bureau, the city has an area of 31.34 square miles (81.17 km2), of which, 31.19 square miles (80.78 km2) is land and 0.15 square miles (0.39 km2) is water. Demographics 2020 census As of the census of 2020, there were 100,200 people. The population density was 2,992.7 inhabitants per square mile. The racial makeup of the city was 81.2% White, 0.6% Black or African American alone, 1.0% American Indian or Alaskan Native alone, 0.9% Asian alone, 0.4% Native Hawaiian or Pacific Islander alone, 5.6% two or more races, 24.8% Hispanic or Latino. 69.6% of people identified as White alone, not Hispanic or Latino. The median age was 33 years old.

Star is a city in northwestern Ada County, Idaho, with parts stretching into neighboring Canyon County. The population was 11,117 at the 2020 census, up from 5,793 in 2010. It was named in the 19th century by travelers on their way to Middleton and Boise who used the star on the school house to find east and west. The name stuck and it became Star, Idaho.

on the school house to find east and west. The name stuck and it became Star, Idaho. Today, it is a rapidly growing suburb of Boise and its schools are shared with Middleton School District and West Ada School District. Star is part of the Boise metropolitan area. Geography Star is located at 43°41′39″N 116°29′25″W (43.694084, -116.490225), at an elevation of 2,470 feet (753 m) above sea level.

2000 census As of the census of 2000, there were 1,795 people in 631 households, including 485 families, in the city. The population density was 2,092.5 inhabitants per square mile (807.9/km2). There were 681 housing units at an average density of 793.9 per square mile (306.5/km2). The racial makeup of the city was 92.87% White, 0.28% African American, 0.95% Native American, 0.22% Asian, 0.06% Pacific Islander, 0.89% from other races, and 4.74% from two or more races. Hispanic or Latino of any race were 4.29%. Of the 631 households 48.0% had children under the age of 18 living with them, 60.2% were married couples living together, 11.7% had a female householder with no husband present, and 23.1% were non-families. 16.8% of households were one person and 4.1% were one person aged 65 or older. The average household size was 2.82 and the average family size was 3.19. The age distribution was 33.2% under the age of 18, 9.9% from 18 to 24, 36.4% from 25 to 44, 14.8% from 45 to 64, and 5.7% 65 or older. The median age was 28 years. For every 100 females, there were 97.0 males. For every 100 females age 18 and over, there were 92.8 males. The median household income was $42,337 and the median family income was $46,458. Males had a median income of $31,028 versus $22,625 for females. The per capita income for the city was $15,864. About 5.4% of families and 8.5% of the population were below the poverty line, including 10.7% of those under age 18 and 13.6% of those age 65 or over. Education All of Star in Ada County is in the West Ada School District (Meridian Joint School District 2).

Meridian is a city located in Ada County, Idaho, United States. The population was 117,635 at the 2020 census, making it the second most populous city in the county and Idaho, after Boise, the state capital.

Rail transportation (1908–28) Following the raising of $4,000 to lay the Interurban rail line from Onweiler (Meridian and Ustick Roads), the tracks were completed into the village center. Turning east on Broadway and ending at East Second, the last car would spend the night in Meridian before returning to Boise early the next morning with passengers and freight. The interurban Station and Generator building (west one-third of the old library at Meridian and Idaho Streets) was built in 1912, and the line continued on to Nampa via Meridian. The tracks down Broadway were not used after 1912. The Interurban Company entered into receivership and closed in 1928 after 20 years of providing continuous transportation to neighboring towns. It was Meridian's main connection to the area outside the local community. The Union Pacific Railroad spur opened in 1900 and is currently operated by the Boise Valley Railroad. Many industrial customers continue to ship forest, agricultural, and chemical products along this corridor. Creamery (1929–70) The city's official website describes the history of the Ada County Dairymen's cooperative creamery as follows:The lowest days of the Great Depression brightened for area dairymen when the Ada County Dairymen's cooperative creamery began operation in 1929. It provided milk checks to those who were members of the cooperative, enabling them to pay their taxes and provide food for their families. Other community members hauled milk to the creamery and were employed by the creamery, whose product was Challenge Butter. The creamery ran seven days a week for 40 years. Additions and improvements were made while the plant was in full operation. Later years saw the Wyeth Laboratories affiliate with the creamery to manufacture SMA baby formula.

Creamery (1929–70) The city's official website describes the history of the Ada County Dairymen's cooperative creamery as follows:The lowest days of the Great Depression brightened for area dairymen when the Ada County Dairymen's cooperative creamery began operation in 1929. It provided milk checks to those who were members of the cooperative, enabling them to pay their taxes and provide food for their families. Other community members hauled milk to the creamery and were employed by the creamery, whose product was Challenge Butter. The creamery ran seven days a week for 40 years. Additions and improvements were made while the plant was in full operation. Later years saw the Wyeth Laboratories affiliate with the creamery to manufacture SMA baby formula.

105, which by 2025 was estimated to have risen to 275,123, making it the second-most populous county in Idaho. The county seat is Caldwell, and its largest city is Nampa. Canyon County is part of the Boise metropolitan area. History Hudson's Bay Company established Fort Boise in 1834 near what is now Parma, but abandoned it in 1855. Emigrants traveled through Canyon County on the Oregon Trail. Discovery of gold in the Boise Basin in 1862 brought settlement to the region again. The lower Boise River was fully contained within Boise County from 1863 until the formation of Ada County in 1864. Settlement of the lower Boise River west of Boise City was limited prior to the completion of the Oregon Short Line Railroad. Middleton was the first European settlement of Canyon County, starting in 1863. The 1870 Census for Ada County listed 76 residents of the Boise Valley, excluding Boise City and the 1880 Census listed 44 residents at Middleton. The arrival of the railroad at Caldwell led to the establishment of a town there as of August 1883. Businessmen James A. McGee and Alexander Duffes filed the plat for nearby Nampa in 1886. Parma was settled around the same time, with the Old Fort Boise post office being moved to the town's location; it was incorporated in 1904. Ada County established precincts for each of the settlements with a combined 1890 Census population of 2,311. Significant settlement of Greenleaf and Notus started around 1904 with the two settlements listed as precincts at the 1910 census. Notus was incorporated in 1921 while Greenleaf was incorporated prior to 1980. Melba was incorporated in 1912 while Wilder was incorporated in 1919. The City of Star annexed a portion of territory in northeast Canyon County prior to 2007, becoming the county's ninth incorporated city. The majority of Star is located within Ada County. The Idaho Legislature created Canyon County from Ada County in an act approved March 7, 1891, effective at the November 26, 1892, election. Caldwell was established as the county seat. The county originally contained all of Canyon and Payette counties and part of Gem; Gem County formed in 1915 and Payette County in 1917.

History Hudson's Bay Company established Fort Boise in 1834 near what is now Parma, but abandoned it in 1855. Emigrants traveled through Canyon County on the Oregon Trail. Discovery of gold in the Boise Basin in 1862 brought settlement to the region again. The lower Boise River was fully contained within Boise County from 1863 until the formation of Ada County in 1864. Settlement of the lower Boise River west of Boise City was limited prior to the completion of the Oregon Short Line Railroad. Middleton was the first European settlement of Canyon County, starting in 1863. The 1870 Census for Ada County listed 76 residents of the Boise Valley, excluding Boise City and the 1880 Census listed 44 residents at Middleton. The arrival of the railroad at Caldwell led to the establishment of a town there as of August 1883. Businessmen James A. McGee and Alexander Duffes filed the plat for nearby Nampa in 1886. Parma was settled around the same time, with the Old Fort Boise post office being moved to the town's location; it was incorporated in 1904. Ada County established precincts for each of the settlements with a combined 1890 Census population of 2,311. Significant settlement of Greenleaf and Notus started around 1904 with the two settlements listed as precincts at the 1910 census. Notus was incorporated in 1921 while Greenleaf was incorporated prior to 1980. Melba was incorporated in 1912 while Wilder was incorporated in 1919. The City of Star annexed a portion of territory in northeast Canyon County prior to 2007, becoming the county's ninth incorporated city. The majority of Star is located within Ada County. The Idaho Legislature created Canyon County from Ada County in an act approved March 7, 1891, effective at the November 26, 1892, election. Caldwell was established as the county seat. The county originally contained all of Canyon and Payette counties and part of Gem; Gem County formed in 1915 and Payette County in 1917.

Adjacent counties Payette County (north) Gem County (northeast) Ada County (east) Owyhee County (south) Malheur County, Oregon (west) National protected areas Deer Flat National Wildlife Refuge (part) Snake River Birds of Prey National Conservation Area (part) Major highways Demographics Racial and ethnic composition 2020 census As of the 2020 census, the county had a population of 231,105. The median age was 34.5 years. 28.0% of residents were under the age of 18 and 14.8% of residents were 65 years of age or older. For every 100 females there were 98.3 males, and for every 100 females age 18 and over there were 95.9 males age 18 and over. The racial makeup of the county was 73.3% White, 0.7% Black or African American, 1.2% American Indian and Alaska Native, 0.9% Asian, 0.3% Native Hawaiian and Pacific Islander, 11.4% from some other race, and 12.2% from two or more races. Hispanic or Latino residents of any race comprised 25.6% of the population. 81.3% of residents lived in urban areas, while 18.7% lived in rural areas. There were 77,829 households in the county, of which 38.4% had children under the age of 18 living with them and 21.6% had a female householder with no spouse or partner present. About 19.3% of all households were made up of individuals and 9.0% had someone living alone who was 65 years of age or older. There were 81,013 housing units, of which 3.9% were vacant. Among occupied housing units, 73.2% were owner-occupied and 26.8% were renter-occupied.