General Patterson, with some 20,000 Union troops—mostly Pennsylvania militia—was at Chambersburg, Pennsylvania, with about an equal number of the Enemy, under General Joseph E. Johnston, at Harper's Ferry, on the Potomac, watching him.

Some 50,000 Union troops were in camp, in and about Washington, on the Virginia side, under the immediate command of Generals McDowell and Mansfield—Lieutenant General Scott, at Washington, being in Chief-command of the Union Armies—and, confronting these Union forces, in Virginia, near the National Capital, were some 30,000 Rebel troops under the command of General Beauregard, whose success in securing the evacuation of Fort Sumter by its little garrison of half-starved Union soldiers, had magnified him, in the eyes of the rebellious South, into the proportions of a Military genius of the first order.

There had been no fighting, nor movements, worthy of special note, until June 7th, when General Patterson advanced from Chambersburg, Pennsylvania, to Hagerstown, Maryland. General Johnston at once evacuated Harper's Ferry, and retreated upon Winchester, Virginia.

General McClellan, in command of the Department of the Ohio, had, however, crossed the Ohio river, and by the 4th of July, being at Grafton, West Virginia, with his small Army of Union troops, to which a greatly inferior Rebel force was opposed, commenced that successful advance against it, which led, after Bull Run, to his being placed at the head of all the Armies of the United States.

Subsequently Patterson crossed the Potomac, and after trifling away over one month's time, at last, on the 15th of July, got within nine miles of Winchester and Johnston's Army. Barring a spiritless reconnaissance, Patterson—who was a fervent Breckinridge-Democrat in politics, and whose Military judgment, as we shall see, was greatly influenced, if not entirely controlled, by his Chief of staff, Fitz John Porter—never got any nearer to the Enemy!

Instead of attacking the Rebel force, under Johnston, or at least keeping it "employed," as he was ordered to do by General Scott; instead of getting nearer, and attempting to get between Winchester and the Shenandoah River, as was suggested to him by his second in command, General Sanford; and instead of permitting Sanford to go ahead, as that General desired to, with his own 8,000 men, and do it himself; General Patterson ordered him off to Charlestown—twelve miles to the Union left and rear,—and then took the balance of his Army, with himself, to the same place!

In other words, while he had the most positive and definite orders, from General Scott, if not to attack and whip Johnston, to at least keep him busy and prevent that Rebel General from forming a junction, via the Manassas Gap railroad or otherwise, with Beauregard, Patterson deliberately moved his Army further away from Winchester and gave to the Enemy the very chance of escaping and forming that junction which was essential to Rebel success in the vicinity of Manassas.

But for this disobedience of orders, Bull Run would doubtless have been a great victory to the Union Arms, instead of a reverse, and the War, which afterward lasted four years, might have been over in as many months.

It is foreign to the design of this work, to present in it detailed descriptions of the battles waged during the great War of the Rebellion —it being the present intention of the writer, at some later day, to prepare and publish another work devoted to such stirring Military scenes. Yet, as it might seem strange and unaccountable for him to pass by, at this time, without any description or comment, the first pitched battle of the Rebellion, he is constrained to pause and view that memorable contest. And first, it may be well to say a word of the general topography of the country about the battle-field.

The Alleghany Mountains, or that part of them with which we have now to do, stretch in three almost equidistant parallel ridges, from North-East to South-West, through the heart of Old Virginia. An occasional pass, or "Gap," through these ridges, affords communication, by good roads, between the enclosed parallel valleys and the Eastern part of that State.