Clermont's name is borrowed from a prefecture in France notable as the home of Celtic leader Vercingetorix who led the unified Gallic resistance to Roman invasion.

Clermont connotes "clear mountain," which describes the hills when viewed through the thick Ohio River fog.

During the Age of Discovery, the French became the first recorded Europeans to see this land from the Ohio River, though Clermont's population dates to the Paleoindian, Adena, Hopewell, and Fort Ancient cultures.

At its ordinance in 1800 by the Commonwealth of Virginia to reward Virginian military veterans with land bounties, Clermont encompassed twenty-three current Ohio counties and over 4.2 million acres of dense old-growth forest.

The last American Indian village was located two miles south of Marathon in Jackson Township, along the mouth of Grassy Run on the East Fork of the Little Miami River.

Clermont's Moscow became the exiled home of French royalty during the early 1800s, including future King of France Louis-Philippe in 1815 and the Marquis de Lafayette in 1825.

[12] Point Pleasant was birthplace and boyhood home of military hero, Union general, and President Ulysses S. Grant, born on April 27, 1822.

His U.S. Senate career lasted from 1833 to 1839, and in 1844, Morris was the vice presidential candidate for a third party with the goal of abolishing slavery—approximately sixteen years before the first antislavery Republican president.

Also in 1844, America's first anarchist, philosopher, and inventor Josiah Warren made Clermont the site of Utopia, an egalitarian haven of Puritans who espoused the doctrines of François Marie Charles Fourier.

[13] The primitive socialist life at Utopia was later made into a musical at the Carnegie Center of Columbia Tusculum.

Grant became commander-in-chief of the U.S. Army in the Civil War, during which John Hunt Morgan and his Confederate raiders invaded Clermont in 1863.

Clermont's last-standing covered bridge was built in 1878 on Stonelick Williams Corner Road, near US Route 50; it was renovated in 2014.

Pattison lived in Milford, and at a time before the influence of Columbus, governed from his home called the Promont, which was used as the official governor's residence.

Orpha Gatch of Milford, the first woman elected to its school board, locally sponsored the county LWV, and is the namesake for the club's award given annually at its suffragist brunch honoring the recognized volunteerism and leadership qualities.

[citation needed] Clermont's congressional seat is occupied by Brad Wenstrup, who resides in Cincinnati, Hamilton County, Ohio.

Encompassing all of Clermont, the 14th Ohio Senate seat is occupied by Terry Johnson, last elected 2020.

Covering northern Clermont, the 65th statehouse seat is occupied by Jean Schmidt, last elected 2020.

Covering southern Clermont, the 66th statehouse seat is occupied by Adam Bird, last elected 2020.

Clermont's elected officers include Debbie Clepper, Recorder; Mark J. Tekulve, Prosecutor; Linda Fraley, Auditor; Robert S. Leahy, Sheriff; Jeremy Evans, Engineer; Paul Kamphaus, Municipal Clerk of Courts; Brian Treon, Coroner; Jeannie Zurmehly, Treasurer; and Barbara Wiedenbein, Common Pleas Clerk of Courts.

The elected Common Pleas Domestic Relations Court is occupied by Judge Mary Lynne Birck.

[40] The result is many developed townships which would have sought shared municipal incorporation with cities or villages have not maximized property value and do not have basic support for services and infrastructure,[41] relying exclusively on reduced state funding—much of which comes from federal investments for roadwork.