Okaloosa County, Florida: History
Okaloosa County was created by an act passed on September 7, 1915, formed from the eastern ranges of Santa Rosa County and the western ranges of Walton County.
Okaloosa means "black water" (oka means "water" and lusa means "black") in the Choctaw language. The name may have come from the related language spoken by the Chatot and other peoples of the Florida Panhandle.