Bullfrog County was created in 1987 out of a portion of southern Nye County to place the proposed high level nuclear waste site in its own county, in an attempt to funnel federal mitigation funds from Nye County to the State of Nevada. It was named after the old Bullfrog Mining District of the nearby Amargosa region. Nye County sued the state and the courts declared the county unconstitutional because it had no residents. It was abolished in 1989.

Carson City, a municipality that also functions as a county was created in 1969. It was named by Frank M. Proctor, one of the founders of Carson City in 1858, directly or indirectly for Christopher "Kit" Carson, the famed guide and explorer, who first entered western Nevada in 1843?44. Carson City became a county as the result of consolidation with Ormsby County in 1969. Ormsby County was created in 1861 and Carson City always served as its county seat. It was named for Major William M. Ormsby, one of the original settlers of Carson City, who was killed in 1860 in the Pyramid Lake Indian War.

Churchill County was created in 1861 and named for Fort Churchill (which was really in Lyon County), which had been named for General Sylvester Churchill, a Mexican War hero who was Inspector General of the U.S. Army in 1861. Churchill County was not organized until 1864, and its county seats were Bucklands (1861-64), LaPlata (1864? 68), Stillwater (1868?1904) and Fallon (1904-present). In the nineteenth century there were several attempts to eliminate Churchill County because of its small population, but Assemblyman Lemuel Allen was able to stop it on all occasions including convincing the Governor to veto the bill after it had been passed by both houses in 1875.

Clark County was created from the southern portion of Lincoln County in 1909 and named for William A. Clark, former United States Senator from Montana, and the builder of the railroad line through the area. Las Vegas has always been its county seat. In 1982 the voters of Nevada voted to amend the constitution to include Clark County within the boundaries of the state, even though Congress added that region to the state in 1867, taking it from Arizona Territory.

Douglas County was created in 1861 and named after Stephen A. Douglas, former United States Senator from Illinois. Douglas is best remembered for his debates with Abraham Lincoln. Douglas was re?elected United States Senator from Illinois over Lincoln in 1858, but was defeated by Lincoln for the Presidency in 1860. Genoa was the county seat until 1916 when it was moved to Minden.

Elko County was created out of western Lander County in 1869. Several explanations have been offered, including an Indian word meaning either "white woman" or "beautiful." Another explanation credits railroad owner Charles Crocker with the naming of a railroad station after elk roaming in the area and adding an "0" to form "Elko."

Esmeralda County was one of the none original counties created in 1861. Esmeralda is the Spanish word for emerald. An early Nevada miner, J. M. Corey, named the Esmeralda Mining District. It is believed that Corey may have named the district after the gypsy dancing girl, Esmeralda, from Victor Hugo's book, The Hunchback of Notre Dame. Esmeralda had three county seats: Aurora until 1883, Hawthorne from 1883 to 1907 and finally Goldfield.

Eureka County was created out of eastern Lander County in 1873 after silver was discovered more than 100 miles east of Austin. The residents of the new mining camp complained that Austin was too far to go for county business and a new county was created. It was named for the ancient Greek term, "Eureka," meaning, "I have found it." This term was used earlier in California and other locations. Eureka has always been the county seat.

Humboldt County is Nevada's oldest county, created by the Utah Territorial Legislature in 1856. It was also one of Nevada's original nine counties created in 1861. Named for the Humboldt River which John C. Fremont named after Baron Friedrich Heinrich Alexander von Humboldt, a German naturalist, traveler and statesman. Humboldt NEVER saw the places that bear his name. Unionville was the first county seat in 1861 until the mining boom died there and it was moved to Winnemucca on the transcontinental railroad line in 1873.

Lander County was one of the original nine counties created in 1861. Named for Frederick W. Lander; chief engineer of a federal wagon route through the area in 1857. He later served as Special Indian Agent in the area, and died during the Civil War in Virginia in 1862 at the rank of brigadier general. Created in 1862, Lander County sprang forth as the result of a mining boom on the Reese River, along the old pony express line; taking a considerable portion of Churchill and Humboldt counties with it. Eventually, Lander would be known as the "mother of counties" because so many were carved out of it. Its first county seat was Jacobsville in 1862 which was soon after moved to Austin in 1863 and finally Battle Mountain in 1979.

Lincoln County was created after Nevada moved it state line eastward and southward at the expense of Utah and Arizona territories. Named for Abraham Lincoln, 16th President of the United States in 1866. The original bill called for the creation of Stewart County, after Nevada Senator William M. Stewart, but the bill was changed in a substitute bill. Crystal Springs was the first county seat in 1861, followed by Hiko in 1867 and Pioche 1871.

Lyon County was one of the nine original counties created in 1861. It was named after General Nathaniel Lyon who died in the Civil War in Missouri in 1861. Its first County Seat was Dayton, which had just changed its name from Nevada City in 1862, which had been called Chinatown before that. After the Dayton Court House burned down in 1909, the seat was moved to Yerington in 1911. There were stories that it was named for Captain Robert Lyon, a survivor of the Pyramid Lake War in 1860, but Archives staff discovered a county seal with the picture of the Civil War general and settled the conflict.

Mineral County was carved out Esmeralda in 1911 shortly after the County seat of Esmeralda was moved to Goldfield in 1907. Its name came from the surrounding area, which is heavily mineralized. Hawthorne has always been its county seat.

Nye County was created in 1864 and named in honor of James W. Nye, Governor of Nevada Territory and later United States Senator from Nevada. Largest county geographically. The first County seat was Ione City in 1864, followed by Belmont in 1867, and lastly by Tonopah in 1905.

Pershing County was created out of Humboldt County in 1919, the last county to be created. It was named for General John J. Pershing, commander?in?chief of the American Expeditionary Force (1917?1919) in Europe during World War 1. Lovelock has always been its county seat.

Storey County was created in 1861 and named for Captain Edward Fariss Storey, who was killed in 1860 in the Pyramid Lake Indian War. It is the smallest county because it had the most people when it was created in 1861. Virginia City was always its county seat. It was originally to be named McClellan County after General McClellan who later ran against Lincoln for President and lost.

Washoe County was created in 1861 as one of the original nine counties. Named after the local Native Americans that inhabited the area. Consolidated Roop County, named for Isaac N. Roop, the Governor of the provisional territory of Nevada, 1859?61. Before that Roop County was known as Lake County after several lakes in the area, including Honey, Pyramid, and Winnemucca. Washoe City was the first county seat in 1861 and was replaced by Reno in 1871. Roop County became part of Washoe in 1883.