After the Confederate defeat at Fort Donelson in February 1862, Nashville surrendered to Union forces. Tennessee Military Governor Andrew Johnson insisted on the fortification of Nashville, a key transportation and supply hub. On August 6, Union Capt. James St. Clair Morton began implementing an elaborate design that made the capital the most heavily defended United States city outside Washington, D.C. More than 2,700 African American laborers constructed Fort Negley, the largest and most complex of Nashville's five major forts.
