Orlando Metcalfe Poe (March 7, 1832 – October 2, 1895) was a United States Army officer and engineer in the American Civil War.

Pfau's sons Adam and Andrew were noted for their skirmishes with Native Americans in southern Beaver County, Ohio.

The brothers’ exploits were detailed in volume II of Theodore Roosevelt’s book, The Winning of the West from the Alleghenies to the Mississippi, 1777 - 1783.

At the start of the American Civil War, Poe assisted in organizing the volunteers from Ohio; later, he was made a member of Major General George B. McClellan's staff in western Virginia and took part in the Battle of Rich Mountain.

In his capacity as chief engineer of the XXIII Corps, he was a key factor in the defense of a siege on Knoxville, Tennessee, led by General James Longstreet, which culminated in the November 29, 1863, Battle of Fort Sanders.

Poe directly supervised the dismantling of all buildings and structures in Atlanta that could have provided any military value to the Rebels once Sherman abandoned the city; rail depots, roundhouses, arsenals and storage areas were manually disassembled and the combustible materials then destroyed by controlled fires (however, Poe was incensed at the level of uncontrolled unsanctioned arson by marauding soldiers not of his unit which resulted in heavy damage to civilian homes.)

Poe was indispensable (by the commanding general's own words) during the march, when Sherman cut loose from his supply lines headed southeast across the body of Georgia to Savannah, living off the land, to bring fire and pillage to the center of the Confederacy.

[5] As superintending engineer, he designed a unique lighthouse—in terms of location, construction materials, methods, hardships and costs—at the Spectacle Reef Light on Lake Huron.

[8] The exposed crib of the Stannard Rock Light is rated in the top ten engineering feats in the United States.

Poe died in Detroit on October 2, 1895, of an infection following an on-duty accident at the "Soo Locks," and was buried at Arlington National Cemetery.