Hartselle is the second largest city in Morgan County, Alabama, United States, 13 miles (21 km) south of Decatur. It is part of the Decatur Metropolitan Area and the Huntsville-Decatur Combined Statistical Area.

Morgan County is a county in the north-central part of the U.S. state of Alabama. As of the 2020 census, its population was 123,421. The county seat is Decatur. On June 14, 1821, it was renamed in honor of American Revolutionary War General Daniel Morgan of Virginia. It is a prohibition or dry county, although alcohol sales are allowed in the cities of Decatur, Hartselle, and Priceville. Morgan County is included in the Decatur, AL Metropolitan Statistical Area, which is also included in the Huntsville-Decatur-Albertville, AL Combined Statistical Area. It is a part of the North, Northwest, and North-Central regions of Alabama.