[3] Grady County is part of the Oklahoma City, OK Metropolitan Statistical Area.

Grady County was part of the land given to the Choctaw by the Treaty of Dancing Rabbit Creek, in exchange for property in the southeastern United States.

[3] Before the Civil War, Randolph B. Marcy blazed the California Road through this area, reporting a Waco and a Wichita village.

At the end of the Civil War, the Five Civilized Tribes and the Caddo, Delaware, Kiowa, Comanche, Apache, Cheyenne, Arapaho, and Osage signed a peace agreement and pledged to stand united against any unjust demands that the federal government made at the war's end.

[3] The first railroad in this area was built to the town of Minco in 1890 by the Chicago, Kansas and Nebraska Railway.

In 1892, the Rock Island built a track connecting Chickasha, Ninnekah, and Rush Springs to the Texas border.

[3] The 1898 Curtis Act stripped the Chickasaw Nation of its authority, and communal land was forced into allotment, paving the way for statehood.

The following sites in Grady County are listed on the National Register of Historic Places: