Forrest's Cavalry Corps was a cavalry formation of the Confederate States Army in the Western Theater of the Civil War commanded by Lieutenant General Nathan Bedford Forrest.

Formed during the summer of 1862, it took part in the various battles in the Western Theater during the second half of the war. At first serving as part of the Army of Tennessee, both Forrest and the corps were then transferred to northern Mississippi and often launched independent raids into Union occupied western and central Tennessee.

In May 1863, Nathan Bedford Forrest was given the cavalry command of Earl Van Dorn, who had recently been murdered. The corps initially consisted of the divisions of William H. Jackson and Frank C. Armstrong but Jackson's division was soon sent to Mississippi, leaving Forrest with only Armstrong's division. On September 3, Braxton Bragg, commander of the Army of Tennessee, gave Forrest the division of John Pegram and placed him in command of all the cavalry north of Chattanooga. During the early stages of the Chickamauga Campaign, Forrest's corps served on the army's right as a rear guard during the retreat from Chattanooga, while Forrest himself was wounded during the fighting. The corps covered the right flank of D. H. Hill's corps during the Battle of Chickamauga, earning praise from Hill. On the morning of September 21, following the Confederate victory in the battle, Forrest rode towards Chattanooga with four hundred men and found that the Union army was still in chaos; he urged Bragg to attack the city immediately but Bragg instead settled in for a siege of the Union garrison.

"General Forrest, I wish to congratulate you and those brave men moving across that field like veteran infantry upon their magnificent behavior . . . No one can speak disparagingly of such troops as yours."

During the early stages of the Chattanooga campaign, Bragg ordered Forrest to transfer the majority of his corps to Joseph Wheeler's cavalry corps, which was about to raid the Union supply lines into Chattanooga. Much has been made of Forrest threatening Bragg, the famous story comes from John Wyeth’s 1899 biography: The Life of General Nathan Forrest. The official records seem to show a respectful relationship between Bragg and Forrest. The original source was James Cowan, a surgeon in the Confederate army and Forrest’s cousin who was the only actual eyewitness. However, Cowan’s recounting suggests that Jefferson Davis was also there, which is not possible. In Wyeth’s second edition, he removed this story.

Whatever actually happened, Bragg transferred three of Forrest’s brigades into Wheeler’s Corps, but not Forrest himself. Forrest had asked to be transferred back to West TN in late August, with a battery, his escort and a battalion of Cavalry, which is exactly what Bragg did, so no reason to even confront him.

The local Union commanders attempted to surround the Confederates in Jackson but Forrest managed to retreat back to Mississippi at the end of December. Once in Holly Springs, he organized his recruits into a cavalry corps with two divisions commanded by James R. Chalmers and Abraham Buford. Forrest was promoted to major-general but Chalmers did not want to serve under him and threatened to leave his command. Chalmers was convinced to remain with Forrest.

The first test of his new cavalry corps began with General Sherman's Meridian Expedition that culminated in the Battle of Meridian. While Sherman moved 20,000 infantry from Vicksburg, General William Sooy Smith was to lead a large force of Union cavalry from Collierville, TN, and meet him at Meridian while destroying the railroad and the crops in the rich prairie. General Forrest moved his cavalry into position and struck the Union cavalry from three directions at Battle of Okolona on February 22. This was a minor victory but it was good practice for more raids out of Memphis by Union cavalry. On March 16, Forrest launched another raid into western Tennessee to capture Union supplies for his corps and to allow his Kentucky and Tennessee troops to return home. Forrest established his headquarters at Jackson and from there, he moved his brigades to attack Union installations: Union City, TN, on March 24; Battle of Paducah (Fort Anderson), Kentucky, on March 24; and Battle of Fort Pillow (also known as the Fort Pillow massacre) on April 12, which ended with a massacre of African-American Union troops and their white officers attempting to surrender. On May 2, his corps began their return into central Mississippi.