[2] Created in 1901 as part of Oklahoma Territory, the county is named for the Caddo tribe who were settled here on a reservation in the 1870s.

Caddo County was organized on August 6, 1901, when the Federal Government allotted the Kiowa, Comanche, and Arapaho reservations and sold the surplus land to white settlers.

Part of its land was taken at statehood to form neighboring Grady County.

By 1960, Caddo County ranked first in Oklahoma for producing of peanuts, hogs and poultry.

[4] The county mostly lies in the Gypsum Hills and the Red Bed plains physiographic areas.

However, while Democrats had a large plurality of registered voters through the 2010s, the county has recently been swept up in the growing Republican trend throughout Oklahoma.

John McCain (2008), Mitt Romney (2012) and Donald Trump (2016) each received at least 64% of the county's vote.

Caddo County is home to cattle ranching and significant wheat and peanut farm operations—with a few of the producers practicing environmentally friendly no-till or reduced tillage farming methods.

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