Idaho History Timeline

By | May 12, 2022

Nomadic big game hunters inhabited the area now known as Idaho about 12,000 years ago. Around 5,000 years ago cultures with permanent homes emerged and around 1500 years ago bow and arrows came into use.

By the 1700s, there was evidence of the Nez Perce in northern Idaho and the Shoshone in the Serpent River plains and mountains to the south.

After the Louisiana Purchase in 1803, the Lewis and Clark Expedition was sent to investigate get including Idaho roles. They crossed into northern Idaho in 1805. Sacagawea , a teenage Shoshone who helped lead the expedition, was born in Idaho.

British opened a trading post in 1809 and fur traders from all over the world came to trade Native Americans for furs. The Oregon Trail crossed southern Idaho in 1843, bringing American settlers to the area.

In the 1846 Treaty of Oregon, the British ceded their claims to the lands, which included the area now known as Idaho, and established the northern boundary at the 49th parallel. When Oregon was admitted as the 33rd state in 1859, all of Idaho was included in the Washington Territory.

Idaho’s first permanent settlement was Franklin, founded by Mormons in 1860. A huge rush of settlers and businessmen followed the discovery of gold in the same year. Most of the settlers came from Washington, Oregon and California. The influx of settlers was large enough to force Congress to create the Idaho Territory in 1863 with capital in Lewiston. Two years later the capital was moved to Boise In 1876-77 Nez PercĂ©, led by chief Joseph, made their heroic but unsuccessful attempt to escape to Canada while being pursued by US troops. By the 1880s, all Native Americans in Idaho lived on the reservation. Idaho was admitted as the 43rd state on July 3, 1890, with Boise as its capital. The population at the time was 88,548, but it almost doubled over the next ten years.

  • Topschoolsintheusa: Guides to study in Idaho, including geography, climate, economy, and tourism of the state.
  • A2zcamerablog: Offers general information about Idaho, covering history, population, economy and county list.
  • Campingship: State outline of Idaho, including geography location, state capital, brief history and a list of largest counties by area.

The railroads continued into the Idaho Territory through the late 1800s. Now the minerals that the mines produced could be sent to other states. Many people came to the railroads looking for work.

Government work projects during the Great Depression (1929-1939) resulted in many roads, bridges and recreation projects being developed in Idaho. After World War II, the economy shifted from being primarily agricultural to food processing and manufacturing.

Idaho has been the state’s primary clutter and mining industry since the early 1900s. Idaho ranks high in silver, antimony, lead, cobalt, garnet, phosphate rock, vanadium, zinc and mercury.

Serpent River was diverted by dams to provide irrigation for Idaho agriculture. Only three states watered the land more than Idaho. The state produces about one quarter of the national potato crop, as well as wheat, apples, corn, barley, sugar beets and hops. In the 1990s, Boise became a center of technology.

Tourism now surpasses other industries in revenue. The natural beauty of the Idaho mountains , rivers, lakes, and streams provide camping, boating, and fishing sites, and they collectively bring in tens of thousands of visitors each year.

Idaho timeline

Photo and USA set Idaho’s southern border at the 42nd parallel

  • (1823)Battle fought in Lemhi Valley between Serpent River explorers and Piegan Indians
  • (1824)US received the Northwest Territory from Russia in a treaty
  • (1832)First crossing the Rocky Mountains in covered wagons; the battle of the Hole of Pierre between the fur hunters and the Grosventre Indians
  • (1843)Oregon Trail set in Idaho
  • (1852)Gold discovered on the River Oreyll
  • (1854)Twenty-one immigrants massacred in the Boise Valley by Serpent River Indians
  • (1863)Idaho Territory organized; Bear the River Massacre, the largest massacre of the West Indians, took place
  • (1865)Boise became the capital of Idaho
  • (1877)Nez Perce Indian Wars took place
  • (1878)Indian tortilla wars were fought
  • (1880)Lead and silver hoards were found in the Wood River area
  • (1890)July 3 Idaho became the 43rd state; the first session of the Idaho legislature met
  • (1897)Bitterroot Forest Reserve was established to protect the bison1900s
  • (1906) The largest sawmill in the US began operations in Potlatch
  • (1910) Wildfires consumed one-sixth of Idaho’s forests, destroyed many communities
  • (1915) Arrowrock Dam completed
  • (1917) Statewide prohibition went into effect
  • (1924) Craters of Lunar National Monument erected; Black Canyon Dam completed
  • (1931) State Income Tax Act passed
  • (1934) Idaho hit US number one in silver production
  • (1935) Statewide Prohibition Revoked
  • (1942 Japanese Americans were placed in internment camps at Hunt
  • (1949) National Reactor Test Station near Arco established
  • (1955) Arco, Idaho, became the first city to be lit by nuclear power
  • (1960) Seven-month strike by miners at Bunker Hill Mine; wildfires in Canyon City and Idaho Ada
  • (1961) Ernest Hemingway died in Ketchum
  • (1972) Underground light fire at Kellogg killed 91
  • (1976) Teton Dam collapsed, killing 11 and forcing over 300,000 to evacuate
  • (1980) Northern Idaho covered in volcanic ash from St. Helens in Washington; 18-hour Idaho State Penitentiary riot causes $2 million in damages
  • (1983) Earthquake in Lost Valley killed two and caused millions of dollars in damage
  • (1985) Grasshopper infestation destroyed large areas of farmland
  • (1989) Wildfires burned thousands of acres in south central Idaho; Idaho lottery has started
  • (1991) Kirby Dam passed out, power cut off to residents, arsenic, mercury, cadmium dumped in Boise River
  • (1992) Shoot caused $3.2 million in Capitol damages; worst wildfire season in Idaho history
  • (1994) Fires burned approximately 750,000 acres; Picabo Street wins Olympic silver medal in downhill
  • (1995) Picabo Street became the first American to win the World Championship oblique title
  • (1996) Northern Idaho hit with major floods
  • (1997) New Year’s Eve floods hit southwestern Idaho


  • (2000) 559,183 acres burned in wildfires
  • (2001) 24 counties declared drought disaster areas
  • (2003) The longest legislative session in history lasted 118 days
  • (2005) Nez Perce Water Agreement ratified, the tribe received annual rights to 50,000 acre-feet of water from the Clearwater River and $80 million in cash.
  • (2007) Idaho has had more fires burning than any other state, damaging over 1.5 million acres.
  • (2009) Idaho has had more fires burning than any other state, over 1.5 million acres damaged; SEC and Commodity Futures Trading Commission sued Darren Palmer, 22 Trigon Group, accused him of running a classic Ponzi scheme that took $68 million from 55 investors
  • (2010) Nine missionary Baptists from Idaho were arrested and faced kidnapping while trading charges in Haiti for the attempted rescue of 33 Haitian earthquake-traumatized children, they were later released
  • (2010) Idaho becomes first state to pass legislation to waive federal mandatory health insurance requirement
  • (2011) Governor issued a statewide declaration of disaster after flooding occurred in the northern and southeastern parts of the state caused by melting thick snow cover
  • (2011) Idaho Falls resident Oscar Ramiro Ortega-Hernandez accused of firing a White House machine gun accused of trying to assassinate President Obama and/or his staff

Idaho History