Idaho City was founded in December 1862 as “Bannock” (sometimes given as “West Bannock”), amidst the Boise Basin gold rush during the Civil War, the largest since the California gold rush a dozen years earlier.

Near the confluence of Elk and Mores Creeks, its plentiful water supply allowed it to outgrow the other nearby camps in the basin, such as Placerville, Pioneerville, and Centerville.

As its population swelled, the new Idaho Territorial legislature changed the town's name to “Idaho City,” to avoid confusion with Bannack, in present-day Beaverhead County, the southwestern corner of Montana.

Wood was the prime source of both shelter and heat, which caused Idaho City to burn four times: 1865, 1867, 1868, and 1871.

During the boom, the greater Boise Basin population numbered in the tens of thousands, but most departed the mountains once mining declined.

The modern economy relies mainly on hunting and fishing tourism, and visits to the many historic sites, including the Boot Hill Cemetery.

Senator Frank Church announced his candidacy for the Democratic nomination for president from the porch of the county courthouse in Idaho City in March 1976.

Chase Clark, Church's father-in-law, had announced his candidacy for governor in Idaho City in 1940.

Annie Lee was one legendary Idaho city woman who like Polly Bemis, escaped from sexual slavery.

She escaped from a member of the Yeong Wo Company in the 1870s to Boise to marry her lover, another Chinese man.

Charged by her owner with grand larceny, she told a judge that she wanted to stay in Boise City.

[13][14] The historic buildings include: According to the United States Census Bureau, the city has a total area of 0.67 square miles (1.74 km2), all of it land.

[15] Idaho City experiences a fairly typical Inland Northwest continental Mediterranean climate (Köppen Dsb) with cold, snowy winters and warm, dry summers, typified throughout by large diurnal temperature variations.

Owing to its more exposed location and slightly higher altitude, it is not only noticeably cooler but also much wetter than Boise, receiving twice as much precipitation and almost four times as much snowfall, which averages 69.1 inches (175.5 cm) with a maximum daily snow depth of 74 inches (188.0 cm) in February 1949.

As of the census of 2020 and the 2022 American Community Survey,[20] there were 466 people, 319 households, and 226 families residing in the city.

The city has an employment rate of 58.6%,with 23.5% of the population holding a high school diploma and 9.7% a bachelor's degree or higher.

The highway travels through the Boise National Forest and is designated as the “Ponderosa Pine Scenic Byway.”[25] The route ascends to Banner Creek Summit at 7,056 feet (2,151 m) and later enters the Sawtooth National Recreation Area about 12 miles (19 km) northwest of Stanley.