On June 26, Maj. Gen. John Pope was placed in command of the newly constituted Union Army of Virginia. Pope deployed his army in an arc across Northern Virginia. Its right flank, under Maj. Gen. Franz Sigel, was positioned at Sperryville on the Blue Ridge Mountains, its center, under Maj. Gen Nathaniel P. Banks, was located at Little Washington and its left flank under Maj. Gen. Irvin McDowell was at Falmouth on the Rappahannock River. Part of Banks's corps, Brig. Gen. Samuel W. Crawford's brigade and Brig. Gen John P. Hatch's cavalry, were stationed beyond the Union line, at Culpeper Court House.