Private Jacob Maill was mustered into Confederate service on May 1st, 1862 when he was enlisted as a Private in Captain Smith’s Company (Key West Avengers), 7th Regiment Florida Infantry by Major R. B. Thomas at Tampa, Florida for a period of 3 years or the war. He is reported present on all rolls until October, 1862, when he was reported to have deserted to Union forces near Versailles, Kentucky. Private James Mosier deserted with him.

According to Roberts Watson’s diary, Maill arrived in a group of some 1,000 Union prisoners of war at Savannah, Georgia on September 28th, 1864.

"Jacob Mall[sic], a young fellow who deserted from the Yankees in Key West in 1862 and came to Tampa and joined our company is among the prisoners. He deserted from our company while in Kentucky in 1862 and joined the Yankees again. We would never had known that the fellow was there but the fool made himself known and wanted to join our service again, for [Joseph] Cole reported him to the Comdg. Officer who sent Cole into the stockade and brought him out and lodged him in jail. I expect he will be shot, he certainly deserves it." -Campbell, R.Thomas (2002). Southern Service on Land and Sea: The Wartime Journal of Robert Watson CSA/CSN. The University of Tennessee Press. p. 207. ISBN 1572331933.