On May 23, Jackson successfully captured the town of Front Royal located in Warren County—an important area which had been held by Union forces under General Banks. This was a great blow to Banks as well as to his troops who rapidly retreated to Winchester. A unique feature of this battle was that among the opposing forces was the First Maryland Regiment, U. S. A. being attacked by the First Maryland Regiment, C. S. A. (Confederate States of America).
Two days later, Jackson rushed Banks at Winchester and surprised his troops to such an extent that they were routed from the town and driven across the Potomac in panic. Jackson who had been ordered by Lee to strike at Banks unexpectedly and to create the impression that it would be utterly impossible for him to converge with Fremont had carefully and painstakingly carried out such an order. Jackson is considered by many as second in military stature only to Lee himself.
On May 31-June 1, 1862 the Battle of Seven Pines or Fair Oaks took place. The left wing of the Union army under McClellan was attacked by Confederate General Joseph E. Johnston at Fair Oaks Station and Seven Pines, located just east of Richmond. The Confederates won at Seven Pines but were driven back at Fair Oaks. The Battle of Seven Pines was considered indecisive. General Johnston was wounded seriously in this battle, and, at this time, General Robert E. Lee was put in command of the Army of Northern Virginia.
On June 8-9, Jackson was slowly retreating up the Shenandoah Valley when he decided to prevent two Union generals, John C. Fremont and James Shields, from combining forces by checking or holding back Fremont and then attacking Shields. He sent part of his troops under General Richard S. Ewell to attack the forces under Fremont at Cross Keys in Rockingham County. General Ewell defeated the forces of Fremont very badly and kept Fremont's help completely away from Shields. Jackson then led his remaining forces north of Port Republic and encountered Shields there. Bitter fighting followed. Shields was eventually defeated and driven down the Shenandoah Valley. This was the final engagement of the so-called Valley campaign. Jackson had proven himself a great military man who had fought on both sides of the Shenandoah Valley and who had marched approximately 700 miles in seven weeks in almost continuous fighting with one or more of the Federal fighting forces. This campaign included five major engagements: Kernstown, McDowell, Front Royal, Winchester and Port Republic. Jackson suffered defeat only at Kernstown by the Union General James Shields. Jackson then proceeded toward Richmond to prevent General McClellan from entering there.
On June 11, General Lee dispatched General James Ewell Brown ("J. E. B.") Stuart with 1200 cavalry and infantrymen from Richmond to obtain information behind the lines of the enemy concerning the specific position of McClellan. In three days, Stuart and his contingent had courageously ridden completely around the army of McClellan, acquiring much valuable information for General Lee. Only one of Stuart's men was killed during the assignment. Based upon the information furnished by General "J. E. B." Stuart, General Lee decided to advance his army on June 26. The Union forces under General Fitz-John Porter had outposts near Richmond just north of the Chickahominy River in the town of Mechanicsville. Confederate General Ambrose P. Hill successfully occupied Mechanicsville and then continued to attack General Fitz-John Porter's troops along Beaver Dam Creek where he severely defeated them.
From June 26 to July 2, the Seven Days' Battle occurred. This included the fighting at Mechanicsville and at Gaines' Mill. In these two skirmishes, Lee, after severe fighting, drove the right wing of McClellan's army under General Porter across the Chickahominy River. At Glendale, Confederate Generals James Longstreet and Ambrose Hill fought terrific hand-to-hand skirmishes with gun butts and bayonets against the rearguard of the forces under McClellan. At nightfall, the Confederates retreated to Malvern Hill. On the following day, the forces under McClellan set up infantry fire with cannon fire just preceding it at the top of the hill. As the separate Confederate detachments charged up the steep hill, they were literally mowed down by the thousands. McClellan retreated during the night to Harrison's Landing. In spite of these military maneuvers, the army under McClellan was finally forced to retreat at the end of the Seven Days' battle, and Richmond, the "City of Seven Hills," still remained in Confederate control.
On August 9, as Jackson was on his way to encounter the Union General, John Pope, who had started southward, he unexpectedly met Union General Nathaniel P. Banks near Cedar Mountain (later called "Slaughter Mountain"), located just south of Culpeper. Severe fighting resulted, and the forces under Jackson had almost been annihilated when they received reinforcements which pushed the Union forces back. Since the number of casualties was extremely high during this battle, Jackson allowed Banks to bury his dead the following day.
On August 30, the Union troops made a second attempt to capture Manassas. Jackson defeated Union General Pope in the Second Battle of Manassas or Second Battle of Bull Run, after destroying large quantities of his supplies. When the Confederate troops had used all their available ammunition, they used stones until reenforcements under General James Longstreet arrived. These soldiers forced the Union troops under Pope to retreat to Centerville and eventually to Alexandria.
On September 5, 1862, General Lee, believing the time was suitable for invading the North, advanced across the Potomac River into Maryland. As they approached Frederick, they sang and marched to "Maryland, My Maryland" but this gesture did not result in large numbers of Marylanders joining the Confederate armed troops as they had hoped. After Jackson had successfully captured Harper's Ferry, Lee moved his remaining troops to Antietam Creek near Sharpsburg, Maryland. Severe fighting with McClellan's troops resulted and the Confederate forces in this area finally were forced to recross the Potomac River into Virginia.