Camp Dennison was a military recruiting, training, and medical post for the United States Army

United States Army

The United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...

 during the American Civil War

American Civil War

The American Civil War was a civil war fought in the United States of America. In response to the election of Abraham Lincoln as President of the United States, 11 southern slave states declared their secession from the United States and formed the Confederate States of America ; the other 25...

. It was located near Cincinnati, Ohio

Cincinnati, Ohio

Cincinnati is a city in the U.S. state of Ohio. Cincinnati is the county seat of Hamilton County. Settled in 1788, the city is located to north of the Ohio River at the Ohio-Kentucky border, near Indiana. The population within city limits is 296,943 according to the 2010 census, making it Ohio's...

, not far from the Ohio River

Ohio River

The Ohio River is the largest tributary, by volume, of the Mississippi River. At the confluence, the Ohio is even bigger than the Mississippi and, thus, is hydrologically the main stream of the whole river system, including the Allegheny River further upstream...

. The camp was named for Cincinnati native William Dennison

William Dennison (Ohio governor)

William Dennison, Jr. was a Whig and Republican politician from Ohio. He served as the 24th Governor of Ohio and as U.S...

, Ohio's governor at the start of the war.

With the outbreak of the Civil War in 1861, George B. McClellan

George B. McClellan

George Brinton McClellan was a major general during the American Civil War. He organized the famous Army of the Potomac and served briefly as the general-in-chief of the Union Army. Early in the war, McClellan played an important role in raising a well-trained and organized army for the Union...

, commander of Ohio's state militia

Militia

The term militia is commonly used today to refer to a military force composed of ordinary citizens to provide defense, emergency law enforcement, or paramilitary service, in times of emergency without being paid a regular salary or committed to a fixed term of service. It is a polyseme with...

, was charged by Governor Dennison with selecting a site for a recruitment and training center for southern Ohio, a possible target for the Confederate States Army

Confederate States Army

The Confederate States Army was the army of the Confederate States of America while the Confederacy existed during the American Civil War. On February 8, 1861, delegates from the seven Deep South states which had already declared their secession from the United States of America adopted the...

 due to its Ohio River location and proximity to slave states such as Kentucky

Kentucky

The Commonwealth of Kentucky is a state located in the East Central United States of America. As classified by the United States Census Bureau, Kentucky is a Southern state, more specifically in the East South Central region. Kentucky is one of four U.S. states constituted as a commonwealth...

 and Virginia

Virginia

The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there...

, from which invasions could be launched.