Short on supplies, Steele sent a detachment commanded by Colonel James M. Williams on April 17 to forage for 5,000 bushels of corn that were reported to be in the area.

In the April 30 Battle of Jenkins' Ferry, men from the 2nd Kansas Colored Infantry Regiment murdered Confederate soldiers in revenge of the massacre at Poison Spring.

Major General Nathaniel P. Banks led the army forces, and Rear Admiral David Dixon Porter was in charge of naval operations.

[3] To support this movement, Union troops commanded by Major General Frederick Steele were tasked with moving south from Little Rock to Shreveport, in what became known as the Camden Expedition.

The Camden Expedition involved two Union forces beginning the campaign independently and joining during the march: Steele started from Little Rock, while Brigadier General John M. Thayer left Fort Smith, Arkansas.

On April 9, Thayer's column joined Steele's; protracted skirmishing between the two sides occurred over the next few days in the Battle of Prairie D'Ane.

[16] Price's cavalry hovered around Camden, unwilling to directly attack due to the disparity in numerical strength but lying in wait of any patrols or foraging parties sent from the Union command.

[12] The Confederate force consisted of three understrength cavalry divisions, which were commanded by Brigadier Generals John S. Marmaduke, James F. Fagan, and Samuel B.

Only one of the steam-powered gristmills in the area remained usable; Steele sent part of the 36th Iowa Infantry Regiment to operate it on April 17.

The Confederates had a special dislike for Kansas troops in general, as the soldiers from that state had a reputation for excessive pillaging and destruction.

[29] That morning, 4 miles (6.4 km) east of White Oak Creek, Williams's men were joined by a relief column sent by Thayer.

[31] The historian Michael J. Forsyth considers the decision to assign Maxey to the operation to be an example of Price's lack of attention to detail.

[36] The success of the operation depended on Maxey's men arriving on time for their part of the attack; Marmaduke's position was also at risk of further Union troops sallying forth from Camden and striking the roadblock in the rear.

[26] Williams's men encountered the roadblock and reported it to their commander, who ordered the wagons to be positioned in a compact formation north of the road.

[38] Maxey ordered his two brigades, commanded by Colonels Charles DeMorse and Tandy Walker, to dismount and advance up the back side of the ridge that bordered the field.

[40] DeMorse's men were ordered to shift west, which forced Walker's brigade to move as well; this caused delays.

[43] Maxey's artillery component, Krumbhaar's Texas Battery, had been unable to position itself on the ridgeline in time to support the attack due to difficulty moving the guns through vegetation on the ridge.

[44] Between Marmaduke's artillery and Krumbhaar's battery, the Confederates had 12 cannon, which were positioned to bring crossfire on the Union lines, in a barrage that last for about half an hour.

[46] The cavalry probe was repulsed and took up a position between the 1st Kansas Colored and the relief column;[47] the force's commander was wounded in the attack.

[51] The James rifle facing south was withdrawn after most of its gun crew was shot or left to take cover, but a round of double-shotted canister from it halted Maxey's men long enough to prevent its capture.

[52] DeMorse and Greene fought the 1st Kansas Colored at close range, while Cabell's men drove in Union skirmishers to the east.

[60] The 18th Iowa, supported by fragments of the 1st Kansas Colored, conducted a fighting withdrawal, making stands at successive ridgelines north of the road.

The Union troops abandoned their cannons when terrain was reached that the guns could not be moved over and continued for Camden via a circuitous route, pursued by the Confederates for 2.5 miles (4 km).

[64] Some of the Union troops ran into the position of the 2nd Arkansas Cavalry east of the battlefield, while others forced a civilian at gunpoint to guide them back to Camden away from the Confederates.

Walker stated that his men were motivated by the thought of shedding "the blood of their despised enemy", and DeMorse's report included the statement that "few prisoners were brought in by my command".

[81] He also describes the massacre as the "worst war crime ever committed on Arkansas soil",[77] and concludes that the killings represented "an ongoing program of racial intimidation" to control the behavior of slaves, instead of random acts of violence.

[85] The paper's editor, John R. Eakin, later published an editorial regarding Confederate response to the Union's use of African-American soldiers stating that "we cannot treat Negroes taken in arms as prisoners of war" and that "our soldiers are not bound to receive their surrender"; an article published by the journal American Journalism in 2005 suggests that Eakin was rationalizing the massacre at Poison Spring.

[91] Smith transferred three divisions of infantry from Louisiana to fight against Steele; the Confederate infantrymen crossed the Red River on April 15 and 16.

[94] Men of the 2nd Kansas Colored Infantry Regiment, in response to the massacre at Poison Spring, executed several prisoners captured from Ruffner's Missouri Battery,[95] and cut the throats of Confederate wounded lying on the field.

[96] The officers of the 2nd Kansas Colored had, after Poison Spring, sworn that "the regiment would take no prisoners as long as the Rebels continued to murder our men".