When the Civil War broke out, the federal government needed to raise and train an army large enough and skilled enough to overcome the revolt in the south. Hundreds of thousands of willing volunteers stepped forward, first as militiamen, then as long-term volunteer soldiers. However, experienced military veterans capable of training such a force were in very short supply. The south, and in particular Virginia, had a similar, enthusiastic response to the prospect of war, and it also possessed a much larger pool of experienced personnel capable of drilling eager volunteers into disciplined soldiers. That edge, combined with the advantages of being on home ground, led to the narrow, but important, victory of the rebel forces at the First Battle of Bull Run. Out of that battle emerged a rebel general with a new nickname, Stonewall Jackson. Having been charged with defending the Shenandoah Valley before making his famous stand at Bull Run, he went back to Winchester with the same orders, to defend western Virginia from the advance of the Union armies. The Union soon sent a portion of its new volunteer force into western Maryland to defend the Baltimore & Ohio Railroad and the Chesapeake & Ohio Canal.

In March 1862 those forces, under the command of Major General Nathaniel Prentiss Banks, were ordered to advance into the Shenandoah Valley and engage the men led by Jackson. What followed transformed Jackson in the eyes of many in the north, and of virtually everyone in the south, from a skilled tactician into a mythical hero. He drove Banks back into Maryland, and subsequently defeated two other Union forces sent to fight against him. Jackson then left the valley to help Robert E. Lee drive the Union's Army of the Potomac away from Richmond. Succeeding there, Stonewall returned to central Virginia, where he again attacked the forces commanded by Banks and John Pope. After a bloody engagement at Cedar Mountain, Jackson brilliantly flanked Pope's army, forcing its withdrawal to the old Bull Run battlefield, where he united with the rest of Lee's army and drove Pope back into the defenses of Washington, DC. For the next eight months, Jackson fought with Lee's Army of Northern Virginia, at Antietam, at Fredericksburg, and most famously organizing and leading an audacious flank attack, which led to the great rebel victory at Chancellorsville where Jackson was mortally wounded.

Among the many men who volunteered for the Union in 1861 were nearly 1,000 who came to form the 46th Pennsylvania Volunteer Infantry. Immediately assigned to the newly-organized command of Nathaniel Banks, it would be their fate, along with the other men assigned to what became the Union Twelfth Corps, to fight against Stonewall and his men for the next twenty months of the war, from their first assignment guarding the C&O Canal, on and on until they entered the very woods at Chancellorsville where Stonewall was to meet his fate. They would continue on to Gettysburg, where they would fight the men of Stonewall's command one final time. They fought against what was perhaps the most skilled and determined force of men the Confederacy ever put on a battlefield, and they did so time again at a frightfully heavy cost, at Cedar Mountain alone suffering fifty percent casualties, and at Chancellorsville nearly a third. And yet, in the end this group of unsung soldiers managed to survive Stonewall and go on to win the war for the Union they held sacred. As seen through the eyes of the men on the front line, this is their story, of the men who fought and survived Stonewall.