The 1st Maryland Cavalry Battalion or better known as Cole's Cavalry was an independent cavalry unit that operated in Western Maryland, West Virginia, and the Shenandoah Valley in Virginia during the American Civil War. They gained a reputation as one of the best cavalry units in that theatre of the war fighting Confederate forces under such notable commanders as John Mosby, Turner Ashby, and Bradley T. Johnson.

This episode highlights Union Joint Operations on the lower Potomac River from 1862 to 1865. The Army and Navy continue their cooperation after the Confederate Blockade of Washington through the cooperation at the Battle of Fredericksburg. After Fredericksburg in December 1862 through May 1865 most Union Joint Operations were in Virginia's Northern Neck including the manhunt for John Wilkes Booth.

While the Confederate Army built fortifications for batteries on the lower Potomac to cut off Union shipping to Washington, a new Union Commander in Chief is appointed by President Lincoln. The Union Army and Navy cooperation to remove the batteries is uneasy as the Lincoln Administration struggles to get General George McClellan to act in removing the Confederate batteries from the Potomac.

This is the first of three episodes that describes Union Combined Operations of the Army and Navy on the lower Potomac River from 1861 to 1865. Episode 1 deals with the collaboration between the Union Army and Navy to secure Washington from Confederate infiltration during the first six months of the Civil War.