Early in 1862, Gen. George B. McClellan, who had kept the Army of the Potomac inactive through the winter, proposed a plan for transporting his troops by sea to Urbana, near the mouth of the Rappahannock River, and from there advancing on Richmond. This plan was soon rendered unfeasible by the advance of the Confederate army under Joseph E. Johnston to the Rappahannock, so McClellan chose Fort Monroe (at the tip of the peninsula between the York and James rivers) as the debarkation point for his offensive. President Lincoln, who preferred an overland advance, reluctantly agreed to McClellan's plan, provided that a force was left behind to protect Washington. The 1st Corps, under Irvin McDowell, was detached from the Army of the Potomac for that purpose.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.