[1] The county was founded in 1798 and named for Albert Gallatin, the Secretary of the Treasury under President Thomas Jefferson.

[2][3] Gallatin County is included in the Cincinnati-Middletown, OH-KY-IN Metropolitan Statistical Area.

The population of Gallatin County in 1800 was 1,291, according to the Second Census of Kentucky, composed of 960 whites, 329 slaves, and 2 "freemen of color".

[5] During the Civil War, several skirmishes occurred in the county and the Union Army arrested a number of men for treason for supporting the Confederates.

The 1866 Gallatin County Race Riot happened just after the Civil War, when bands of lawless Ku Klux Klansmen terrorized parts of the Bluegrass State.

"[6] On December 4, 1868, two passenger steamers, the America and the United States, collided on the Ohio River near Warsaw.

The combined death toll was 162, making it one of the most deadly steamboat accidents in American history.

It was unusual as Benjamin and Mollie French were killed for the murder of Lake Jones, another, older African-American man.

[7] As the 20th century progressed, commercial river trade began to decline, and the steamboat era ended, as faster means of transportation became available.

Rail lines expanded, automobiles and trucks became reliable, and aircraft soon arrived on the scene.

In the postwar period after World War II, numerous major highways were constructed, leading to greater auto travel and commuting.

Marco Allen Chapman was executed in 2008 for multiple murders he committed on August 23, 2002, in Warsaw, Kentucky.

[11] A third child, daughter 10-year-old Courtney Sharon, played dead after being stabbed and then escaped.