As the border states began to fall, Alabama iron became critical to the survival of the Confederacy. During the last two years of the war, Alabama's furnaces were producing 70% of the entire southern iron supply.
That output invited federal invasion in the largest cavalry operation of the war. Known as Wilson's Raid, a federal force of over 14,000 laid waste to Tannehill and a dozen other Alabama furnaces including the Selma Arsenal as the war came to an end.
The Tannehill Ironworks was attacked by three companies of the 8th Iowa Cavalry under the command of Capt. William A. Sutherland on March 31, 1865. Before leaving, they torched all the adjacent factory buildings, slave cabins, a large gristmill and tannery and a storehouse for food and supplies. In the fire, Tannehill's workforce of over 500 slaves and white mechanics was scattered and displaced. A mile downstream on Roupes Creek, the Williams & Owen Forge escaped detection.
Sutherland re-joined Brig. Gen. John T. Croxton's main force of 15,000 cavalrymen which proceeded on to burn the University of Alabama in Tuscaloosa. En route on April 1, Croxton's cavalry engaged CS troops commanded by Brig. Gen. William H. (Red) Jackson in the battle of Trion (now called Vance).
While iron production ended at Tannehill in 1865, its main financier, John Alexander, continued to operate the cupola furnace producing products from iron scrap before the site was sold to the Thomas iron interests of Pennsylvania, a parent company of Republic Steel Corp., in 1868.
Listed as a Designated site on the Civil War Preservation Trust's National Discovery Trail.