February 3–April 8, 1863
The Yazoo Pass Expedition was a failed Union attempt to advance on Vicksburg, Mississippi, in the spring of 1863.
By late 1861, President Abraham Lincoln was pressuring Union commanders in the west to invade the South. In early 1862, Brigadier General Ulysses S. Grant's forces gained control of two of the three main rivers connecting the North and South in the Western Theater by capturing Fort Henry, located on the Tennessee River, and Fort Donelson, located on the Cumberland River.
Promoted to major general on February 16, 1862, for his achievements, Grant soon turned his attention to controlling the Mississippi River. If the Union could secure dominion over the Mississippi, the Confederacy would be divided and denied easy access to supplies from the Gulf of Mexico and territories in the American West. Admiral David Farragut captured the port city of New Orleans on May 18, 1862, closing down Confederate access to the Gulf. In June, the Union tightened its grip on the Mississippi when Federal forces captured the river city of Memphis, Tennessee. Nevertheless, the South still controlled traffic on much of the river because of its strong fortifications at Vicksburg, Mississippi.
Vicksburg is located on the eastern side of the Mississippi, roughly fifteen miles south of the mouth of the Yazoo River. The city was known as "The Gibraltar of the Confederacy" because it is situated on a high bluff overlooking a horseshoe-shaped bend in the river. The bluff upon which the city sits made it nearly impossible to assault from the river. Farragut made two attempts to do so in May and June 1862, but both excursions failed.
In December 1862, a Federal attempt to capture the city by land failed miserably when Major General John C Pemberton's Confederate forces mauled Major General William T. Sherman's Federals at the Battle of Chickasaw Bayou (December 26–29, 1862).
Undeterred by Sherman's setback, Grant hatched another operation in the late winter of 1863 to advance on Vicksburg, known as the Yazoo Pass Expedition. On February 3, 1863, Union engineers breached a levee on the Mississippi River about 300 miles north of Vicksburg, flooding a channel that previously connected the Mississippi River to the Tallahatchie River via Moon Lake and the Coldwater River. The channel, including its connected waterways, was known as the Yazoo Pass.
With the navigable connection created, a naval flotilla of two ironclads, six gunboats, and two rams, commanded by Lieutenant Commander Watson Smith, passed through the gap on February 24, 1863, and began steaming toward the Tallahatchie River. Smith's expedition also included troop transports carrying 4,500 Union soldiers from the 13th Army Corps, commanded by General Leonard F. Ross.
On February 9, 1863, Confederate General John C. Pemberton, commander of the Army of Vicksburg, learned about the Union expedition. He immediately dispatched a small contingent of soldiers to fell trees and otherwise hinder the progress of the Federal flotilla,; which was already moving excruciatingly slow due to natural obstructions and Lieutenant Commander Smith’s lack of urgency.
As concern about the newest threat to Vicksburg traveled up the Confederate chain of command all the way to President Jefferson Davis, Pemberton sent Major General William W. Loring's 1,500-man division up the Yazoo River to halt the Yankees in February.
Loring arrived at Greenwood, Mississippi, on February 21, 1863. He quickly began constructing defenses at the junction of the Tallahatchie and Yazoo Rivers, about four miles downriver from Greenwood. By March 11, Loring's men had created a series of artillery batteries, protected by earthworks and cotton bales, which were connected by lines of rifle pits and entrenchments. The largest gun in Loring's arsenal was a 32-pounder that had a clear field of fire nearly two miles up the Tallahatchie River, from where the Union flotilla would be coming. In addition to the breastworks, Loring's soldiers constructed an obstructing raft to block the river, and they scuttled a ship named the Star of the West in the channel to further impede navigation. The Rebels named the formidable stronghold Fort Pemberton, but the Federals referred to it as Fort Greenwood.
On March 11, 1863, the Confederate batteries opened fire on Smith's flagship, the USS Chillicothe, as it rounded the last bend in the river above Fort Pemberton. The salvo caused considerable damage to the Chillicothe, forcing a quick withdrawal. Over the next next five days the Union naval forces made two more unsuccessful attempts to subdue the Rebel stronghold. On March 17, Lieutenant Commander Smith reported himself unfit for duty due to illness, and Lieutenant Commander James P. Foster, captain of the Chillicothe, assumed command of the expedition. After consulting with General Ross, Foster decided that any further attempts to subdue Fort Pemberton would be futile. On March 18, Foster ordered the flotilla to return to Helena, Arkansas, on the Mississippi.
As the Yankees withdrew upriver after their loss at the Battle of Fort Pemberton, they encountered Union Brigadier General Isaac F. Quinby, leading part of his division downstream to reinforce the expedition. Quinby assumed command of all the army forces and ordered them back downstream. He intended to disembark near Fort Pemberton and then send the transports upstream to return with the rest of his division in preparation for a land assault against the Rebel stronghold. Spearheaded by the naval gunboats, the assault on March 23 had barely begun before it was halted when the Chillicothe struck an underwater mine and withdrew.
Even before this latest failure to subdue Fort Pemberton, General Grant began to have second thoughts about the expedition. On March 22, 1863, Grant notified Major General James B. McPherson that "The party that first went in have so delayed as to give the enemy time to fortify. I see nothing for it now but to have that force return the way they went in." Five days after Quinby's unsuccessful assault, Grant formally cancelled the Yazoo Pass Expedition. On March 28, Grant informed Brigadier General Benjamin M. Prentiss, Quinby's commander, "The troops that have gone down the Yazoo Pass are now ordered back." Prentice passed the message down the chain of command and Quinby began the withdrawal on April 5. The flotilla cleared the Yazoo Pass on April 8, 1863, ending the expedition.
Loss of life during the Battle of Fort Pemberton was minimal. Each side suffered fewer than twenty casualties (killed, wounded, missing/captured).
Although the Yazoo Pass Expedition was a military failure for the Union, it did inflict some economic hardship on the Confederacy. The breach in the levee on the Mississippi River flooded thousands of acres of farmland, causing a Confederate loss of 4,000 to 5,000 bales of cotton, plus other staples, and an estimated financial loss of over one million dollars.