Meanwhile the work of building fortifications of earthworks, begun by Colonel Giddings' 56th Regiment of Militia, had so far progressed that there were three forts on elevated ground on different sides of Leesburg. One, known as Fort Evans, named in honour of Brigadier General Nathan G. Evans, in command of the Leesburg neighborhood, was on the heights on the part of the original Exeter between the Alexandria Pike and the Edwards' Ferry roads, recently purchased by Mr. H. B. Harris of Chicago from Mrs. William Rogers and Mr. Wallace George; another, known as Fort Johnston, in honour of General Joseph E. Johnston, commander of a portion of the Confederate troops at the first battle of Manassas, (Bull Run), crowned the hill now covered by the extensive orchards of Mr. Lawrence R. Lee, about one and one-half miles west of Leesburg on the Alexandria Road; and the third, known as Fort Beauregard, was constructed south of Tuscarora in the triangle formed by the old road leading to Morrisworth, the road to Lawson's old mill and Tuscarora. The property is now owned by the heirs of the late Mahlon Myers.
All of these fortifications were, at the time, considered of great potential importance but in the course of events none, save for a long-distance bombardment of Fort Evans on the 19th October, 1861, were destined ever to be attacked nor, therefore, defended. The remains of all remain largely in place, useful only as local monuments to Loudoun's most tragic era.
The principal engagement in the county between the hostile armies took place in the first year of the war. Soon after the first battle of Manassas (Bull Run) the Leesburg neighborhood was held for the Confederates by Brigadier General Nathan G. Evans and his 7th Brigade made up of the 8th Virginia Infantry under Colonel Eppa Hunton; the 13th Mississippi, under Colonel William Barksdale; the 17th Mississippi, under Colonel W. S. Featherstone, together with a battery and four companies of cavalry under Colonel W. H. Jenifer, all sent there by General Beauregard to protect his left flank from attacks by General McClellan, whose forces lay across the Potomac, and to keep open communications with the Confederate troops in the Valley.