It was the first county in the United States to elect a female sheriff, Pearl Carter Pace.

[6] Major waterways include the Cumberland River and a small branch of Dale Hollow Lake which covers the southern end of the county.

As of 2017 the largest self-identified ancestry groups/ethnic groups in Cumberland County, Kentucky were:[14] [14] Like all of the heavily Unionist eastern Pennyroyal, a region of largely small farms that did not rely heavily on slavery, Cumberland County provided an exceptionally large number of soldiers for the Union Army during the Civil War.

[16] Reflecting that, the county became and has remained overwhelmingly Republican following the end of the Reconstruction Era.

[17] The last Democrat to carry Cumberland County at the Presidential level was Horatio Seymour in 1868.

Lyndon Johnson, in his 1964 landslide, is the only Democrat to receive 40% of the county's vote in a presidential election since 1896.