The armies gather
In the days following the Battle of Fort Sumter, the Union capital at Washington, D.C., strengthened its defenses and secured its railway connection with the North through Baltimore via the Baltimore and Ohio (B&O) railway. Washington’s other significant rail line, the Orange and Alexandria, ran southwest to Lynchburg, Virginia; control of this line would be much contested in the days to come. It was joined at Manassas Junction, 30 miles (48 km) southwest of Washington, by the Manassas Gap railway from Strasburg in the Shenandoah Valley.
Robert E. Lee, commanding the Virginia state forces, was loath to become the aggressor in the expanding conflict and refrained from attacking Washington or supporting Confederate sympathizers in Baltimore. U.S. Pres. Abraham Lincoln had proclaimed a blockade of Confederate ports (April 19) and called for 42,000 three-year volunteers and 40,000 more men to join the regular army and navy (May 3). Lincoln was awaiting the result of Virginia’s referendum on secession (May 23) and scrupulously avoided any violation of Virginian territory, although Federal troops crossed the Potomac (May 24) and, without opposition, occupied the south bank for the protection of the capital. Although Winfield Scott, the commanding general of the Union army, had little faith in state militia units, he proposed to use them to defend Washington and recover the Federal garrison at Harpers Ferry, while he trained the newly raised volunteers for an autumn campaign.