Caldwell County is a county located in the U.S. state of Kentucky. As of the 2020 census, the population was 12,649. Its county seat is Princeton. The county was formed in 1809 from Livingston County, Kentucky and named for John Caldwell, who participated in the George Rogers Clark Indian Campaign of 1786 and was the second lieutenant governor of Kentucky. Caldwell was a prohibition or dry county until 2013, when the citizens voted to lift the ban.

Princeton is a home rule-class city in Caldwell County, Kentucky, in the United States. It is the seat of its county. The population was 6,329 during the 2010 U.S. Census. Princeton is home to several notable attractions such as Adsmore Museum, Champion-Shepherdson House, University of Kentucky Research and Education Center Botanical Garden, Capitol Cinemas, the Annual Black Patch Festival, and Newsom's Aged Kentucky Ham.