Enlisted in Company G, 11th Arkansas Infantry of Confederate Army on December 29, 1862. Legend says he and a friend were captured by Union soldiers but escaped and ran to river where they pushed a bale of cotton across the river. Dennis was hit in the back and paralyzed. His friend got him home however, but he was paralyzed from the waist down the remainder of his life.

Actual records, however, show that Dennis was in Port Hudson, LA Confederate Hospital in 1863 with tuberculosis. He was discharged on Sep 22, 1863 as being physically unable to perform his duties.