Three Civil War battles took place in south central Arkansas in the spring of 1864 as part of the Union Armys Red River Campaign. The sites of these skirmishes Poison Springs, Marks Mills, and Jenkins Ferry and the 1836 Courthouse at Historic Washington State Park, which served as Arkansass Confederate capital, comprise the Red River Campaign National Historic Landmark.

On April 20, 1864, a 150-wagon supply train from Pine Bluff reached the Union soldiers. Upon learning that Confederate forces, now joined by General Edmund Kirby Smith's army from Louisiana, had crossed the Ouachita River downstream, Steele felt it safe to send the train, plus 60 additional wagons, in a northward direction back to Pine Bluff for more supplies. This time, though, he sent an escort force of more than 1,200 men, including 240 cavalry and six artillery pieces.

After this devastating blow, General Steele abandoned all intentions of marching to Shreveport on his way to capture Texas, and began to plan his retreat from Camden back to Little Rock. The only escape route he knew was Military Road that ran north through Princeton and Jenkins Ferry, the final section of the Red River Campaign. Marks' Mills Battleground State Park features interpretive exhibits and picnic sites.