Arkansas Post was founded in 1686 by Henri de Tonti at the site of a Quapaw Indian village named Osotouy near where the Arkansas River enters the Mississippi River. The site was a strategic point for France, Spain, the United States, and the Confederate States at different times during its history.
On 17 April 1783 British Colonel James Colbert conducted a raid against Spanish forces controlling Arkansas Post as part of a small campaign against the Spanish on the Mississippi River. Colbert's Raid was the only Revolutionary War battle fought in Arkansas.
In 1803 Arkansas Post became a part of the United States as part of the Louisiana Purchase. The post was selected as the first capital of the Arkansas Territory and became the center of commercial and political life in Arkansas. Prior to statehood the territorial capitol was moved to Little Rock, Arkansas and Arkansas Post lost much of its importance.
During the American Civil War the Post became an important strategic site as it was the confluence of two major rivers. In 1862 the Confederate Army constructed a massive earthwork known as Fort Hindman named after Confederate General Thomas C. Hindman. In January of 1863 Union forces conducted an amphibious assault on the fortress backed by ironclad gunboats and destroyed both the fort and the civilian areas of Arkansas Post.
The former site of Arkansas Post was made into a State Park in 1929. In 1960 the site was designated as a National Memorial and as a National Historic Landmark. In 1966 Arkansas Post was added to the National Register of Historic Places.