18th Indiana Infantry Regiment in the American Civil War

Overview

The 18th Indiana Infantry (Three Years’ Service) was an infantry regiment from Indiana that served in the Union Army during the American Civil War. Organized at Indianapolis, Indiana, the regiment was mustered into Federal service on August 16, 1861, for a three-year term. The unit participated in campaigns across the Western and later Eastern Theaters, serving with distinction in several major battles and operations.

The regiment was notable for its early service in Missouri and Arkansas, its participation in the Vicksburg Campaign, and later actions in Louisiana, Texas, and Virginia. The 18th Indiana Infantry reenlisted as a veteran regiment in early 1864 and continued active service until mustering out in August 1865.

Organization & Service

The 18th Indiana Infantry (Three Years’ Service) was organized at Indianapolis and mustered in on August 16, 1861. The regiment departed Indiana the following day for St. Louis, Missouri, and joined Fremont’s forces, participating in operations in Missouri. It subsequently moved with Pope’s army to the Blackwater, contributing to the capture of a significant number of Confederate prisoners.

In February 1862, the regiment marched to Cross Hollow, Arkansas. In March, during an engagement near Leesville, its brigade played a key role in saving another Union brigade from capture, with the 18th Indiana recapturing the guns of the Peoria artillery. The regiment advanced at Elkhorn Tavern (Battle of Pea Ridge), helping to drive Confederate forces from the field. It then marched to Helena, Arkansas, engaging at Cotton Plant in July before reaching Helena on July 13, 1862.

In October, the regiment moved to southeastern Missouri for winter quarters. In spring 1863, it was transferred to Grant’s army, participating in the engagement at Grand Gulf. At Port Gibson, the regiment captured a stand of colors and artillery, and was engaged at Champion’s Hill, Black River Bridge, and throughout the Vicksburg siege, including the assault on enemy works where it was among the first to reach the parapet.

Following Vicksburg, the 18th Indiana took part in the Bayou Teche campaign and other operations in Louisiana during the fall of 1863. On November 12, it embarked for Texas, participating in actions at Mustang Island and Fort Esperanza. The regiment reenlisted at Indianola, Texas, in January 1864, and was furloughed home, stopping at Baton Rouge to help repel a Confederate threat.

In July 1864, the regiment was ordered to Virginia, joining General Butler’s forces at Bermuda Hundred and engaging in skirmishes at Deep Bottom. It was then transferred to Washington, D.C., and assigned to the 2nd Division, 19th Corps, which joined Sheridan’s army in the Shenandoah Valley. The 18th Indiana fought at the Opequon (Third Winchester), Fisher’s Hill, and Cedar Creek, suffering significant casualties. In January 1865, the regiment was sent by transport to Savannah, Georgia, where it spent three months constructing fortifications. On May 3, it was detached and sent to Augusta, Georgia, where it raised the U.S. flag over the arsenal. The regiment returned to Savannah on June 7, served in southern Georgia, and was mustered out on August 28, 1865.

Engagements & Campaigns

• Fremont’s Missouri Operations (1861)
• Blackwater (1861)
• Cross Hollow, Arkansas (February 1862)
• Leesville, Arkansas (March 1862)
• Battle of Pea Ridge / Elkhorn Tavern (March 1862)
• Cotton Plant, Arkansas (July 1862)
• Grand Gulf (April 1863)
• Port Gibson (May 1863)
• Champion’s Hill (May 1863)
• Black River Bridge (May 1863)
• Siege of Vicksburg (May–July 1863)
• Bayou Teche Campaign (Fall 1863)
• Mustang Island, Texas (November 1863)
• Fort Esperanza, Texas (November 1863)
• Deep Bottom, Virginia (July–August 1864)
• Battle of Opequon / Third Winchester (September 1864)
• Fisher’s Hill (September 1864)
• Cedar Creek (October 1864)
• Operations at Savannah and Augusta, Georgia (1865)

Casualties

• Original strength: 1,056
• Gained by recruits: 140
• Reenlistments: 359
• Total served: 1,555
• Loss by death: 180
• Desertion: 53
• Unaccounted for: 156

Casualty figures are based on regimental and state records. At the Battle of Opequon, the regiment lost 54 killed and wounded; at Cedar Creek, 51 killed and wounded and 35 captured.

Field Officers & Commanders

• Colonel Thomas Patterson
• Colonel Henry D. Washburn
• Lieutenant Colonel Henry D. Washburn
• Lieutenant Colonel DeWitt C. Thomas
• Lieutenant Colonel Jesse L. Holman
• Lieutenant Colonel William S. Charles
• Lieutenant Colonel James C. Black
• Lieutenant Colonel Josiah Campbell
• Major DeWitt C. Thomas
• Major Jesse L. Holman
• Major John C. Jenks
• Major Jonathan H. Williams
• Major James C. Black
• Major Napoleon H. Daniels

Regimental Roster

The complete roster of soldiers who served in the 18th Indiana Infantry (Three Years’ Service) is available for genealogical and historical research. This roster includes names, ranks, and service details as recorded in official state and regimental records.

To view the full roster, visit the 18th Indiana Infantry (Three Years’ Service) Roster page.

Sources & References

• Official Records of the Union and Confederate Armies, Series I, Volumes 8, 13, 17, 24, 26, 34, 39, 43
• Indiana Adjutant General’s Report
• Dyer, Frederick H., A Compendium of the War of the Rebellion
• Fox, William F., Regimental Losses in the American Civil War
• The Union Army, Federal Publishing Company, 1908, Volume 3