In November 1861, Confederate troops began to build a defensive fort that would control the river approach to Clarksville.
[2] The Union took over the fort and enlarged it so that it would control traffic on the Hopkinsville (Kentucky) Pike.
In April 1862, this small garrison was made up of the 71st Ohio Volunteers commanded by Col. Rodney Mason.
The town and fort were reoccupied by Federal troops who remained for the rest of the war.
[6] The city of Clarksville dedicated a new $2 million Fort Defiance Interpretive Center in 2011 in time for the 150th anniversary of the start of the American Civil War in 2011.