Confederate Army of the Shenandoah Harpers Ferry, Virginia (modern day West Virginia). To organize and train the companies, Virginia state commander Robert E. Lee initially appointed Thomas J. Jackson to command the post. Jackson formed five regiments of infantry and a battery of artillery from the various companies, forming the basis of the Stonewall Brigade. On May 15, Joseph E. Johnston replaced Jackson as commander of Harpers Ferry and continued to receive additional regiments from throughout the Confederacy. He would eventually have four brigades of infantry and an independent regiment of cavalry, the 1st Virginia Cavalry commanded by J. E. B. Stuart. In mid-June, forces
Army of Northern Virginia Gen. J. E. Johnston as it was joined by the Army of the Shenandoah on July 20, 1861, when command was relinquished to General J. E. Johnston. The following day this army fought its first major engagement in the First Battle of Manassas. With the merging of the Army of the Shenandoah, Gen. Joseph E. Johnston took command from July 20, 1861, until May 31, 1862. Under the command of Johnston, the Army immediately entered into the First Battle of Manassas. On October 22, 1861, the Department of Northern Virginia was officially created, officially ending the Army of the Potomac.