He marks the location where units from Alexandria left to join the Confederate Army on May 24, 1861. He is facing South, the direction toward many of the battlefields upon which his comrades fell during the War Between the States. His back to the North.
The names of those Alexandrians who died in service for the South are inscribed at the base of the statue. In 1900, the name James W. Jackson was added to the east side of the base.
Jackson was the proprietor of the Marshall House, and he killed Colonel Elmer Ellsworth on the morning of May 24, 1861. He was almost instantly killed by Corporal Francis Brownell.
Nowhere is Ellsworth mentioned--on the statue (I get that) or on the plaque where the Marshall House stood.