[4] Ouachita Parish was the home to many succeeding Native American groups in the thousands of years before Europeans colonized the area.

Notable examples include the Filhiol Mound Site, located on a natural levee of the Ouachita River.

[5] The oldest and most significant is Watson Brake, the most ancient mound complex in North America, dated to 5400 BP (before present), or about 3500 BCE.

Its dating changed archeologists' understanding of the antiquity of mounds in North America and what types of cultures constructed them.

Beginning in the 1750s, Choctaw Indians began hunting in northern Louisiana, including the Ouachita country, expanding from their traditional territory in what is now Mississippi.

Following its defeat in the Seven Years' War, in 1763 France ceded its territories in North America east of the Mississippi River to the victor Great Britain.

In 1769, Alejandro O'Reilly, the first Spanish governor to rule successfully in West Louisiana, claimed Ouachita Parish for Spain.

)[6] He was assigned that year to establish the first European outpost in the area of the Ouachita River Valley, called Poste d'Ouachita.

With his wife, a few soldiers and slaves, his small party made the slow, arduous journey by keelboat up the Mississippi, Red, Black and Ouachita rivers to reach this area.

[7] Originally based in Arkansas, Filhiol surveyed his grant and settled in 1785 at Prairie des Canots (included within the present-day city of Monroe).

[7] Other settlers and merchants were attracted to the trading post, which became known as Fort Miro, with a town developing by 1805, two years after the United States acquired the Louisiana Purchase from France.

The arrival of the powered paddle wheeler was a landmark event, as it connected the town to much easier travel to and from other markets and stimulated its growth.

Following the Reconstruction era, as white Democrats regained control of the state government, they increasingly worked to re-establish dominance over the freedmen in Ouachita Parish.

[9] Among the victims was George Bolden, an illiterate black man "accused of writing a lewd note to a white woman".

[16] The Ouachita Correctional Center (OCC) was opened in 1963, presently houses a maximum of 1,062 offenders, and employs 124 full time deputies.