[3] On June 14, 1821, it was renamed in honor of American Revolutionary War General Daniel Morgan of Virginia.

[4] 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.

The county was created by the Alabama territorial legislature on February 6, 1818, from land acquired from the Cherokee people in the Treaty of Turkeytown, and was originally called Cotaco County.

[5] As of the census of 2020, there were 123,421 people, 46,470 households, and 31,752 families residing in the county.

As of the census of 2010, there were 119,490 people, 47,030 households, and 33,135 families living in the county.

As of the census of 2000, there were 111,064 people, 43,602 households, and 31,437 families living in the county.

[15] According to the census[16] of 2000, the largest ancestry groups in Morgan County were English 60.1%, Scots-Irish 12.71%, and African 11.24% Of the 43,602 households 33.50% had children under the age of 18 living with them, 57.40% were married couples living together, 11.20% had a female householder with no husband present, and 27.90% were non-families.