The battery was formed when Captain John C. Landis recruited men from the Missouri State Guard in late 1861 and early 1862.

After initially serving in the Trans-Mississippi Theater, where it may have fought in the Battle of Pea Ridge, it was transferred east of the Mississippi River.

Eventually, many southerners decided that secession was the only way to preserve slavery, especially after abolitionist Abraham Lincoln was elected president in 1860.

His candidacy was regionally successful, as much of his support was from the Northern States; he received no electoral votes from the Deep South.

[5] In Charleston Harbor, South Carolina, the military installation of Fort Sumter was still held by a Union Army garrison.

[8] Shortly after the attack, Lincoln requested that the states remaining in the Union provide 75,000 volunteers; in the coming weeks Virginia, North Carolina, Tennessee, and Arkansas joined the Confederacy.

Brigadier General Nathaniel Lyon, the commander of the arsenal, moved to disperse the militiamen on May 10 in the Camp Jackson affair; a pro-secession riot in St. Louis followed.

Lyon pursued, although a portion of his command, under Colonel Franz Sigel, was defeated at the Battle of Carthage on July 5.

The plan failed as Sigel was routed and Lyon was killed; the Union troops retreated all the way to Rolla after the defeat.

However, Major General John C. Frémont concentrated Union troops near Tipton, threatening Price's position.

Despite not being able to enlist enough men to bring the battery to full strength, it traveled to Des Arc, Arkansas, in January 1862 to be equipped with cannons.

[3][18] Around this time, the battery was assigned to Brigadier General Daniel M. Frost's artillery brigade and followed the rest of the Army of the West across the Mississippi River in mid-April.

[20] The battery also fought in a skirmish in the vicinity on May 28, which left two soldiers wounded, before the Confederates abandoned the city on the night of May 29/30.

On September 14, Price occupied Iuka, Mississippi, as part of this offensive; additional Confederate forces under the command of Major General Earl Van Dorn were only a four-days' march away.

Major General Ulysses S. Grant, one of the top Union commanders in the region, wanted to avoid the possibility of Price and Van Dorn joining forces.

[24] Landis's Battery was part of Green's brigade of Brigadier General Louis Hébert's division of Price's corps during the battle.

[21] On January 27, 1863, the battery was transferred to Grand Gulf, Mississippi, joining the defenses on the Big Black River.

[21] While stationed at Grand Gulf, the battery participated in several minor engagements with Union gunboats, although some of the artillerymen reported boredom.

[30] In mid-March, the battery guarded a point known as Winkler's Bluff on the Big Black River, with orders to allow no boats to pass.

These soon moved east from the river, leading Brigadier General John S. Bowen, the Confederate commander at Grand Gulf, to send a blocking force to Port Gibson in an attempt to stop the incursion.

[38] Despite it holding initially, Union pressure eventually drove in Bowen's right, causing the Confederates to retreat before Grant outflanked them.

[39] After Port Gibson, the Confederates were forced to abandon their position at Grand Gulf on May 3; Landis's Battery again served as part of a rear guard.

On May 16, Confederate Brigadier General Stephen D. Lee encountered elements of Grant's army during the move east, beginning the Battle of Champion Hill.

[49] The infantrymen of Bowen's Division made an attack against the Union line, and some of the Confederate artillery, including Landis's Battery, moved forward to support the assault.