With the outbreak of the Civil War and the bombardment of Fort Sumter in South Carolina, President Abraham Lincoln called for 100,000 volunteers to put down the growing rebellion.
Colonel Henry B. Carrington had been commissioned to raise troops for the expanded United States Army in Ohio, Indiana, and Pennsylvania.
In July 1861, he established a training camp on the Solomon Beers farm along the Delaware Road, four miles north of the city of Columbus.
For most of the war, Camp Thomas served as the headquarters for the 18th U.S. Infantry, with the roster of the First Battalion being filled by Colonel Carrington and his recruiters in early September.
The camp remained active throughout the war as headquarters for the 18th U.S. Infantry, and served as a training base for fresh recruits needed to refill the ranks after significant combat losses at battles such as Stones River.
Columbus officials hoped that brick or stone buildings would prove more lasting (and keep the base open after the war); they also wanted a military cemetery established for the dead of the 18th U.S. Infantry.