Overview
The 138th Indiana Infantry (One Hundred Days’ Service) was an infantry regiment organized in Indiana for Union service during the American Civil War. Mustered in at Indianapolis in May 1864, the regiment served as part of Indiana’s quota of one hundred days’ troops. Its primary role was to perform guard and garrison duties, relieving veteran units for active campaigning during the summer of 1864. The regiment was composed of seven companies from Indiana’s 9th Congressional district and three from the 11th district.
The 138th Indiana Infantry was mustered into United States service on May 27, 1864, and served primarily in Tennessee, focusing on protecting vital railroad lines and supply routes supporting Union operations in the Western Theater.
Organization & Service
The 138th Indiana Infantry (One Hundred Days’ Service) was organized at Indianapolis, Indiana, in May 1864. The regiment was mustered into service on May 27, 1864, with a total strength of 886 officers and men. Shortly after organization, the regiment departed Indiana for Tennessee.
Upon arrival in Nashville, the 138th Indiana was assigned to guard duty along several key railroads, including the Nashville & Chattanooga, Tennessee & Alabama, and Memphis & Charleston lines. These assignments were critical in maintaining the flow of supplies and reinforcements to Union armies operating in the region, particularly those supporting General Sherman’s campaigns. The regiment’s service consisted largely of garrisoning important points and protecting transportation infrastructure from Confederate raids and sabotage. The 138th Indiana Infantry remained engaged in these duties until late August 1864, serving slightly beyond its original enlistment period. The regiment was mustered out of service in August 1864.
Research This Regiment Further
If you’d like to explore this unit’s history in more depth, regimental histories and Civil War reference works offer valuable detail.
Engagements & Campaigns
- Guard and garrison duty along the Nashville & Chattanooga, Tennessee & Alabama, and Memphis & Charleston railroads (May–August 1864)
- Support of Union supply lines during the Atlanta Campaign (indirectly, through railroad protection)
Casualties
- Killed or died of disease: 8
- Deserted: 1
- Total known losses: 9
Field Officers & Commanders
- Colonel James H. Shannon
- Lieutenant Colonel James W. Dunn
- Major Charles S. Ellis
Regimental Roster
The full roster of the 138th Indiana Infantry (One Hundred Days’ Service), including officers and enlisted men, is available for genealogical and historical research. This roster provides names, ranks, and additional service details where available.
To view the complete roster, visit the 138th Indiana Infantry (One Hundred Days’ Service) Roster page.
Sources & References
- Official Records of the Union and Confederate Armies, Series I, relevant volumes.
- Indiana Adjutant General’s Report.
- Dyer, Frederick H. Compendium of the War of the Rebellion.
- Federal Publishing Company, The Union Army, Vol. 3 (1908).