The Appalousa (also Opelousa) were an indigenous American people who occupied the area around present-day Opelousas, Louisiana, west of the lower Mississippi River before European contact in the 18th century. At various times in their history, they were associated with the neighboring Atakapa and Chitimacha peoples.
The name Opelousas has been thought to have many meanings, but the one most commonly accepted is "Blackleg." The tribe was known for painting or staining their lower legs a dark color.
Michel De Birotte, who lived in Louisiana from 1690 to 1734, about forty years of which he spent living among the Indians, said the Appalousa lived just west of two small lakes. This description is thought to apply to Leonard Swamp (east of present-day Opelousas). During the period, this was the westernmost channel of the Mississippi River. Because of mineral deposits and the great number of leaves covering the bottom, the waters of the lake appeared black. The Appalousa who hunted and fished in the lake found their legs became stained black from these waters.
Language
Dr. John Sibley reported in a 1805 letter to Thomas Jefferson that the Opelousa spoke a language different from all others but many understood Atakapa (itself a language isolate) and French. (This area had been colonized by the French since the mid-18th century.) Their language is completely undocumented.
In the early 20th century, anthropologists John R. Swanton and Frederick W. Hodge tentatively classified the Opelousa language as Atakapa.