On April 9, 1865, the regiment surrendered at the Battle of Fort Blakeley, and was paroled in May when the war ended for all effective purposes.

The First Missouri Brigade, commanded by Colonel Francis M. Cockrell, was transferred to the vicinity of Grand Gulf, Mississippi in early March 1863.

However, the 1st and 4th Missouri (Consolidated) was on detached duty guarding a bridge, and missed the ensuing Battle of Port Gibson on May 1.

[2] After Bowen withdrew from the Port Gibson area, the 1st and 4th Missouri (Consolidated) was next engaged at the Battle of Champion Hill on May 16.

The regiment then charged the Union position, buying time for Brigadier General Martin E. Green's Confederate brigade to arrive.

[4] Together, the brigades of Cockrell and Green, including the 1st and 4th Missouri (Consolidated), charged the Union line, which was driven back some distance.

[5] However, Union reinforcements and a strong line of artillery blunted the charge, and Bowen's men were forced to give up the ground they had gained.

[2] After the retreat from Champion Hill, the 1st and 4th Missouri (Consolidated) was next engaged on May 17, at the Battle of Big Black River Bridge.

[9] At Kennesaw Mountain, the 1st and 4th Missouri (Consolidated) and the rest of Cockrell's brigade was part of the Confederate line at a promontory named Pigeon Hill.

[12] Cockrell's brigade had deployed skirmishers, who were quickly driven in when the Union troops charged the position on Pigeon Hill.

Cockrell's men drove back all of the Union assaults made against their position, and were engaged in combat for about an hour.

General John Bell Hood, now commander of the Confederate army, dispatched French's division, which contained Cockrell's brigade, to capture a fortified Union position at Allatoona Pass.

[19] The First Missouri Brigade was decimated at Franklin, suffering 419 losses out of the 696 engaged in a frontal assault on the fortified Union lines.

[16] After the failure of the Nashville campaign, the 1st and 4th Missouri (Consolidated) was ordered to Mobile, Alabama, where it participated in the defense of Fort Blakeley.

During the Battle of Fort Blakeley on April 9, 1865, the Confederate defenses, including the 1st and 4th Missouri (Consolidated), were overrun by a strong Union assault.