I assume this is your Henry : Pvt. Henry Roark, Co.D 15th Ark.Inf.( from the N.P.S. Civil War Soldier and Sailor Search Site.) This regiment was at Forts Henry and Donelson.
I HOPE this might be your Henry : From the " Family Search "site sponsored by the Morman Church.( http://www.familysearch.org/) Their "International Genealogical Index-North America has a Henry Roark, born abt.1832 in Tennessee.married to a Elizabeth Jane Barnes on 30 July,1856 in Union,Ark. Henry died AFTER 15 FEB.1862. This was about the time of the battles of Forts Henry and Donelson. This site also features the 1880 U.S.Census. From that I found a LISER ( short for Elizabeth ? ) Roark age 41 and son HENRY (Jr.?)18,( born abt 1862 ) living in Arkansas. Hope this helps