Early in April 1861, even before the convention in Richmond had voted to secede, Virginia militia companies from many counties east of the mountains that had been reorganized or reinvigorated after John Brown's raid on Harpers Ferry in October 1859 offered their services to the governor. In some instances they actually marched toward or boarded trains for Richmond while the convention delegates in Richmond were debating and voting for secession. Within days of the convention's vote to secede, Federal forces evacuated the arsenal at Harpers Ferry and the navy yard at Portsmouth, and the Virginia militia soon occupied those installations. After voting for secession the convention appointed field officers for the state's infantry, cavalry, and artillery regiments and began a rapid buildup of the military in anticipation of an invasion. The governor and the convention appointed Colonel Robert E. Lee to the command of all of Virginia's defense forces. He had resigned from the United States Army after being sounded out about whether he would accept the command of the army to suppress the rebellion. Lee traveled to Richmond, where he took command at a ceremony before the convention delegates on April 23, 1861.
In northwestern Virginia and in some communities in the upper valley of the Potomac River, men formed volunteer companies and offered their services to the United States Army, but throughout western parts of the state other Virginia men joined companies to fight for the Confederacy. Fewer white Virginians fought during the Civil War in the United States Army than in the army of the Confederate States, but in many communities, especially in the northern and western portions of the state, family members and friends took opposite sides in the conflict.