John Alexander McClernand was born on May 30, 1812, in Breckinridge County, Kentucky. He and his family moved to Shawneetown, Illinois, in 1813. As a young man, McClernand studied law and joined the Illinois bar in 1832. He also served as a volunteer private in the Black Hawk War that same year. From 1833 to 1834, McClernand worked as a trader on the Mississippi and Ohio Rivers. In 1835, McClernand founded a newspaper, the Shawneetown Democrat, and served as its editor.
McClernand launched his political career in 1836 when voters elected him to the Illinois House of Representatives. They reelected him in 1840 and he served until 1843 when they elected him to the United States House of Representatives. McClernand served in the House until March 3, 1851, when he chose not to seek another term. McClernand returned to Congress in 1859, serving until 1861, when he resigned and volunteered for service in the Union Army. As a politician, McClernand supported Stephen Douglas, and he was a friend of fellow Illinoisan Abraham Lincoln.
Union Army Officer
When President Lincoln called for volunteers on April 15, 1861, McClernand returned to Illinois and raised the “McClernand Brigade.” On May 17, 1861, the War Department commissioned him as a brigadier general of volunteers. Officials sent McClernand to Missouri, where he saw his first action as a brigade commander under Ulysses S. Grant at the Battle of Belmont (November 7, 1861).
Action in the West
In February 1862, Grant promoted McClernand to a divisional commander, and he served in the assaults on Fort Henry (February 6, 1862) and Fort Donelson (February 11 – 16, 1862). For his service at Fort Donelson, the War Department promoted McClernand to major general of volunteers on March 21, 1862. At the Battle of Shiloh (April 6 and 7, 1862), McClernand’s command served primarily in reserve to William T. Sherman’s force.
Dissatisfied with his status serving under Grant, McClernand began using his influence with President Lincoln to promote his advancement. In October 1862, McClernand visited Lincoln in Washington, DC., and asked to receive an independent command. Wishing to maintain the support of Illinois Democrats, Lincoln complied. Secretary of War Edwin M. Stanton authorized McClernand to return to Illinois to raise troops for an assault on the Confederate stronghold of Vicksburg, Mississippi.
Before McClernand finished his recruiting assignment, Grant began his own Vicksburg Campaign. In December, Grant ordered Sherman and over 30,000 Federal soldiers to travel down the Mississippi River, disembark near the mouth of the Yazoo River, and attack Vicksburg from the north. Fewer than 6,000 Confederate defenders easily repulsed Sherman’s assault at the Battle of Chickasaw Bayou (December 26 to 29, 1862), forcing the Federals to withdraw.
In early January, McClernand arrived at the mouth of the Yazoo River with the corps-sized army he had recruited. To Grant’s displeasure, army officials ordered Sherman’s corps to join McClernand’s force to carry out the river assault on Vicksburg.
Battle of Arkansas Post
McClernand named the combined force the Army of the Mississippi. He then launched an attack on Fort Hindman, near Arkansas Post, rather than assault Vicksburg, as he had told Stanton he would do. McClernand’s 33,000-man army easily overran Brigadier General Thomas J. Churchill’s 5,500-man garrison at Fort Hindman during the Battle of Arkansas Post (January 9 to 11, 1863). The Union victory contributed little, if anything, toward the success of the Vicksburg Campaign, but it eliminated a minor impediment to Union shipping on the Mississippi River.
Rivalry with Ulysses S. Grant
Flushed with success and eager for glory, McClernand announced an expedition against the Arkansas capital at Little Rock. Grant, however, was unimpressed with McClernand’s victory and considered it a diversion from the real task at hand. He countermanded McClernand’s plans and ordered him to rejoin the Union campaign against Vicksburg. McClernand complied and army officials relegated him to a corps commander after Grant disbanded the Army of the Mississippi and reassigned its troops to the Army of the Tennessee.
Throughout the rest of the Vicksburg Campaign, the relationship between Grant and McClernand deteriorated. Like other West Point officers, Grant had little respect for politicians-turned-generals such as McClernand. McClernand was angry with Grant for commandeering his army and obstructing his military advancement. As a result, McClernand resorted to a secret campaign of character assassination against Grant, spreading rumors to the press about his superior’s struggle with alcohol.
After the Battle of Champion Hill (May 16, 1863), Grant criticized McClernand’s performance, feeling that he had not contributed enough to the Union victory. By that point, the end of their personal rivalry was just a matter of time. On May 30, McClernand drafted a laudatory message to his corps, claiming much of the credit for the expected fall of Vicksburg. He then released the dispatch to the press, counter to orders from Grant and the War Department.
Relieved of Command and Resignation
Grant used the provocation to relieve McClernand of his command on June 18, 1863, two weeks before the fall of Vicksburg. President Lincoln, still seeking the support of War Democrats, restored McClernand to a field command in the Department of the Gulf in 1864, but health issues convinced McClernand to resign from the Army on November 30, 1864.
After the Civil War, voters elected McClernand as circuit judge of the Sangamon District of Illinois in 1870. He served until 1873. In 1876, he presided over the Democratic National Convention. He later served on a federal advisory board overseeing the Utah Territory.
McClernand died in Springfield, Illinois on September 20, 1900. He was buried at Oak Ridge Cemetery, in Springfield, Illinois.