During the Civil War, Union leaders launched the Red River Campaign because they feared Mexico might try to retake Texas and wanted to cut off Texas as a source of men and supplies. Union Major General N. P. Banks was ordered to advance from New Orleans to Shreveport, while Union Major General Frederick Steele moved from Little Rock through southwest Arkansas toward the same objective. Their plan was to defeat Confederate Major General Edmund Kirby Smith at Shreveport, secure the Red River for navigation, and invade cotton-rich Texas to supply New England textile mills. In Arkansas, this phase became known as the Camden Expedition from Steele's reports, although Shreveport, not Camden, was the true goal. Steele was ordered to carry minimal supplies and live off the countryside, and the resulting shortages became a major problem for his army. Those shortages would make the Battle of Prairie D'Ane the turning point of the Camden Expedition. On March 23, Steele left Little Rock with 8,500 men, while General John Milton Thayer left Fort Smith with 4,500 men to meet Steele in Arkadelphia on April 1. From March 24 to April 1, Steele marched through Benton, crossed the Ouachita River at Rockport, and continued to Arkadelphia, where he waited for Thayer until April 1; when Thayer did not arrive, Steele left Arkadelphia that day. From March 31 to April 2, Confederate General J. S. Marmaduke's 3200 cavalrymen attacked Steele's column from front and rear in a series of actions in Clark County to slow the advance and force the Union army to consume its supplies. On April 3 and 4, Union forces crossed the Little Missouri River at Elkins' Ferry and began an engagement with Marmaduke, who withdrew first to fortifications on high ground and then to Prairie D'Ane. From April 5 to 9, Union forces advanced to high ground and rested at the Cornelius Farm. Fearing Banks was unsuccessful in Louisiana, needing supplies, and believing supplies could be found in Camden, Steele decided on April 5 to go there, and Thayer arrived on April 9.