Army of the Ohio

Army of the Ohio was a principal Union Army formation in the Western Theater of the American Civil War. It was constituted twice, first serving from 1861 to 1862 before being consolidated into the Army of the Cumberland, and later being re-established in 1863 to operate in the Eastern Tennessee and Atlanta Campaign theaters. The army played a crucial role in several pivotal campaigns, including the Battle of Shiloh and the Battle of Perryville, under commanders like Don Carlos Buell and William S. Rosecrans.

History

The initial formation was created in late 1861 from the Department of the Ohio, primarily comprising troops from Ohio, Indiana, Illinois, and Kentucky. This force, under Brigadier General Don Carlos Buell, was instrumental in securing the border state of Kentucky for the Union. Following the Battle of Perryville in October 1862 and subsequent criticism of Buell's leadership, the army was reorganized and renamed the Army of the Cumberland under Major General William S. Rosecrans. The second incarnation was formed in 1863 from the XXIII Corps and other units of the Department of the Ohio, commanded by Major General Ambrose Burnside and later John M. Schofield, serving through the conclusion of the Atlanta Campaign and the Franklin-Nashville Campaign.

Organization

The army's structure evolved throughout its service. Its first iteration was organized into multiple divisions, including the 1st Division under Alexander McDowell McCook and the 2nd Division under Thomas L. Crittenden. Key subordinate formations included the IV Corps and the XIV Corps. The second army was essentially built around the XXIII Corps, often operating alongside the Cavalry Corps of the Military Division of the Mississippi. Its composition included divisions led by officers such as Jacob D. Cox and Alvin P. Hovey, drawing regiments from across the Midwestern United States.

Commanders

Leadership of the army was held by several prominent Union generals. The first commander was Don Carlos Buell from November 1861 until October 1862. William S. Rosecrans briefly commanded during the transition to the Army of the Cumberland in late 1862. The second army was initially led by Ambrose Burnside during the Knoxville Campaign. Command then passed to John M. Schofield in February 1864, who led it through the Atlanta Campaign under William Tecumseh Sherman and the subsequent Franklin-Nashville Campaign against John Bell Hood. Other notable officers who served in its high command included George H. Thomas and Gordon Granger.

Major campaigns and battles

The first Army of the Ohio saw significant action in the early Western Theater. It marched to reinforce Ulysses S. Grant at the Battle of Shiloh in April 1862. Later, it opposed Braxton Bragg's Confederate invasion of Kentucky, culminating in the indecisive but strategic Battle of Perryville. The second army played a key role in the liberation of Eastern Tennessee, notably at the Battle of Fort Sanders during the Knoxville Campaign. As part of Sherman's March to the Sea, it fought in the Battle of Resaca, the Battle of Kennesaw Mountain, and the Battle of Atlanta. It achieved a decisive victory at the Battle of Franklin and contributed to the final destruction of Hood's army at the Battle of Nashville.

Legacy

The Army of the Ohio is remembered for its critical role in maintaining Union control of the vital border states and its contributions to major Union victories in the heart of the Confederacy. Its operations in Kentucky and Tennessee helped secure the Cumberland Gap and major rivers like the Tennessee River. The service of its soldiers from the Midwestern United States was instrumental in the success of the Atlanta Campaign, a major turning point in the war. The army's history is preserved through numerous monuments and historical sites, including those at the Perryville Battlefield State Historic Site and the Franklin Battlefield.

Category:Union armies of the American Civil War Category:Military units and formations established in 1861 Category:1861 establishments in the United States