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. The department comprised three districts: Aquia District, Potomac District, and the Valley District. In April 1862, the department was expanded to include the Departments of Norfolk and the Peninsula (of Virginia). Gen. Johnston was eventually forced into maneuvering the Army southward to the defenses of Richmond during the opening of the Peninsula Campaign, where it conducted delay and defend tactics until Johnston was severely wounded at the Battle of Seven Pines.