Luke C. Lyman was born on October 30, 1832, in Clermont County, Ohio, to Frederick and Hannah Lyman. His father was a miller who owned $100 of personal property by 1860. By 1850, Lyman was working as a shoemaker in Franklin, Ohio. He married Mary Ann Gasten on May 27, 1860, and they had at least four children: Henry, born around 1864; Byron, born around 1866; John, born around 1873; and Anna, born around 1876.
He enlisted in the Union army on October 30, 1861, and he mustered in as a private in Company A of the 18th United States Infantry. According to his enlistment records, he was 5 feet, 10 inches tall, with brown hair and blue eyes. The regiment took part in the Battle of Shiloh, the Battle of Perryville, the Battle of Chickamauga, and the Atlanta campaign. In October 1863, he “cheered at the way Ohio has gone this election,” celebrating Union Party candidate John Brough’s gubernatorial victory over Peace Democrat Clement Vallandigham. He mustered out on October 30, 1864.
He settled in Canaan, Ohio, after leaving the army, and he resumed his job as a shoemaker. By 1870, he owned $500 of personal property. He moved to Denmark, Ohio, in the 1870s, and he worked as a farmer. He applied for a federal pension in August 1882 and eventually secured one. By 1900, he was living in Gilead, Ohio. He died of arteriosclerosis in Edison, Ohio, on March 26, 1922.