The earliest area inhabitants were drawn to the Tennessee Valley for its rich abundance of game and resources. Decatur, incorporated in 1826, remained a rural agricultural center until the 1830s when the railroad brought a new era of growth.
The railroad helped in the development of Decatur, but it also played a role in its devastation. During the Civil War, the northern and southern armies fought for control of the railroad and its bridge across the Tennessee River.
In the 1930s, the Tennessee Valley Authority (TVA) was created, and its programs benefited both the economy of the area and the lifestyle of its residents, providing recreational activities and wildlife preservation projects.