William L.S. Tabor was born in Methuen, Massachusetts, on June 2, 1843, and later relocated to Hampstead, New Hampshire. In September 1862, in response to the call for volunteers following the Battle of Antietam, Tabor enlisted in the Union Army. He was assigned to Company K of the 15th New Hampshire Volunteer Infantry. After training in Concord, his regiment deployed to the Department of the Gulf, arriving in New Orleans in December 1862.

In 1863, Tabor’s unit participated in the Siege of Port Hudson, Louisiana. The conditions were extreme, characterized by tropical disease, heat, and constant combat. During the siege, the 15th New Hampshire was tasked with protecting laborers digging “saps” or approach trenches toward Confederate lines. The Confederates attempted to clear these trenches by rolling short-fused artillery shells down a wooden trough directly into the Union positions.

During one such attack, a Confederate shell killed or wounded 125 men. As the rebels prepared a second shell, Tabor voluntarily leaped atop the sandbag breastworks, fully exposing himself to enemy sharpshooters only feet away. He successfully looped a rope around the wooden trough and jerked it into the Union lines, causing the live shell to roll backward into the Confederate works where it exploded. His quick thinking and bravery saved the lives of the men in the trench.

Tabor remained at the siege lines until the Confederate surrender on July 9, 1863. He was mustered out in August 1863 but chose to reenlist in September 1864 with Company K, 1st New Hampshire Heavy Artillery. He served in the defenses of Washington, D.C., until his final discharge in June 1865. Following the war, he lived in Derry, New Hampshire, where he served as a town custodian, volunteer fireman, and member of the Grand Army of the Republic. Thirty-three years after his act of valor, he was awarded the Medal of Honor.