In the spring of 1864, three Civil War battles took place in south central Arkansas that were part of the Union Army's Red River Campaign. The  three state historic parks commemorating these battles--Poison Springs Battleground State Park, Marks' Mills Battleground State Park, and Jenkins Ferry Battleground State Park--and the 1836 Courthouse at Historic Washington State Park, which served as Arkansas's Confederate capitol--comprise the Red River Campaign National Historic Landmark