- Total 10,227 sq mi (26,490 km2)
- Land 10,181 sq mi (26,370 km2)
- Water 46 sq mi (120 km2)
Highest elevation 14,505 ft (4,421 m)
Lowest elevation -279 ft (−85 m)
Population (April 1, 2010)
- Total 18,546
- Estimate (2016) 18,144
- Density 1.8/sq mi (0.70/km2)
Present day Inyo county has been the historic homeland for thousands of years of the Mono tribe, Coso people, Timbisha, and Kawaiisu Native Americans. They spoke the Timbisha language and the Mono language with Mono traditional narratives. The descendants of these ancestors continue to live in their traditional homelands in the Owens River Valley and in Death Valley National Park.
Inyo County was formed in 1866 out of the territory of the unorganized Coso County, which had been created on April 4, 1864 from parts of Mono and Tulare Counties. It acquired more territory from Mono County in 1870 and Kern County and San Bernardino County in 1872.
For many years it has been commonly believed that the county derived its name from the Mono tribe of Native Americans name for the mountains in its former homeland. Actually the name came to be thought of, mistakenly, as the name of the mountains to the east of the Owens Valley when the first whites there asked the local Paiutes what the name of the mountains to the east was.
The local Paiutes responded that that was the land of Inyo. They meant by this that those lands belonged to the Shoshone tribe headed by a man whose name was Inyo. Inyo was the name of the headman of the Panamint band of Paiute-Shoshone people at the time of contact when the first whites, the Manly expedition of 1849, wandered, lost, into Death Valley on their expedition to the gold fields of western California. The Owens Valley whites misunderstood the local Paiute and thought that Inyo was the name of the mountains when actually it was the name of the chief, or headman, of the tribe that had those mountains as part of their homeland.
“Indian George”, a fixture of many of the stories of early Death Valley days, was Inyo’s son. Indian George’s Shoshone name was “Bah-Vanda-Sa-Va-Nu-Kee”, which means “The Boy Who Ran Away”, a name he was given when he became terrified of the whites and their wheeled wagons and huge buffalo, none of which the Shoshone had ever seen before when they came wandering down Furnace Creek Wash in December 1849. In 1940, when Bah-vanda was around 100 years old, JC Boyles, a Panamint Shoshone who had become educated, came back to the Panamint Valley and interviewed Bah-Vanda at length about the early days of his life, including the events of 1849, and it is in this interview (which can be found in the February 1940 issue of The Desert Magazine) that Bah-vanda refers to his father, Inyo.
In order to provide water needs for the growing City of Los Angeles, water was diverted from the Owens River into the Los Angeles Aqueduct in 1913. The Owens River Valley cultures and environments changed substantially. From the 1910s to 1930s the Los Angeles Department of Water and Power purchased much of the valley for water rights and control. In 1941 the Los Angeles Department of Water and Power extended the Los Angeles Aqueduct system further upriver into the Mono Basin.