Asahel W. Thompson, Jr., was born around 1838 in South Carolina to Asahel and Nancy Thompson. His father was a farmer who owned $1,500 of real estate and $5,050 of personal property by 1860. Thompson grew up in Chesterfield, South Carolina, and he probably moved to Arkansas in the 1850s.
He enlisted in the Confederate army on September 19, 1861, and he mustered in as a private in Company G of the 6th Arkansas Infantry. The regiment took part in the Battle of Shiloh, the siege of Corinth, the Battle of Chickamauga, and the Atlanta campaign. He fell ill during the winter of 1861-62, and he spent the next several months in hospitals in Atlanta, Georgia; Montgomery, Alabama; and Knoxville, Tennessee. He was wounded at Chickamauga in September 1863, but he eventually recovered and rejoined the regiment. He was wounded in the left arm on July 22, 1864, and he died on August 25, 1864.