The 98th Illinois Infantry regiment was organized at Centralia, Illinois. Tasked with recruiting and organizing the regiment, was US Colonel John J. Funkhouser. The soldiers were recruited from the following counties: Clay, Richland, Effingham, Crawford, White and Jasper. They would be mustered into Federal service on September 3, 1862. The 98th would promptly be relocated to Louisville, where they would be assigned to the US Major General Don Carlos Buell’s Army of the Ohio.
By the time it was assigned to the Army of the Ohio, it would miss the main battles, of CS General Braxton Bragg’s Kentucky Campaign. Shortly after Bragg was pushed from Kentucky, commander D.C. Buell would be removed from command of the Army of Ohio. The army would become the Army of the Cumberland, and would have a new commander – US Major General William S. Rosecrans. Old “Rosey” would be well liked by his troops, and was a very pious man – having a Catholic priest on his staff.
The 98th would see its first action, in the operations against Confederate raider, John Hunt Morgan, in eastern Kentucky, from December 22, 1862 to January 2, 1863. On December 23, 1862, fate intervened and the 98th Illinois was assigned to a brigade commanded by Colonel John T. Wilder, from Greensburg, Indiana. The 98th would join the 17th Indiana, 72nd Indiana, 92nd Illinois and 123rd Illinois in what would be known as Wilder’s Lightning Brigade. This hybrid brigade would be mounted infantry, and would be armed with Spencer repeating rifles – financed to each soldier, by a personal guarantee by Wilder.
The 98th Illinois, and the rest of the Lightning Brigade would miss the terrible battle, of Stones River, while they were chasing Morgan, but they would arrive at Murfreesboro, Tennessee the day after the battle.
In June 1863, they would be instrumental in opening Hoover’s Gap, during the Tullahoma Campaign, allowing the Army of the Cumberland to push CS General Bragg’s Army of Tennessee clear into northern Georgia.
In September 1863, the 98th Illinois would participate, with the rest of Wilder’s Lightning Brigade in the Battle of Chickamauga. They would be instrumental in holding off Confederate attacks against the right flank. With their repeating Spencer rifles, they were able to maximize their force against a numerically superior Confederate attacking force. Today, a large monument marks the spot, at Chickamauga, where Wilder’s brigade held back the Rebel attacks.
Following the Army of the Cumberland’s retreat, to Chattanooga, the 98th would be involved in the fighting around Chattanooga, and Ringgold. In the spring and summer, of 1864 they would fight in the Atlanta Campaign – Resaca, Dallas, New Hope Church, Kennesaw Mountain and the siege of Atlanta. After the fall of Atlanta, they would pursue CS Lieutenant General John Bell Hood into northern Georgia.
The 98th Illinois would muster out of Federal service on June 27, 1865. Returning to Springfield, Illinois they would be discharged on July 7. They would suffer a total of 171 casualties during the Civil War.