Elvis was the first musical megastar had a film the civil war drama love me tender(1956). He played in a couple more war movies but that was in the late 1950's and 1960's.
Love Me Tender is the best movie he made in my opinion. So far--it has not yet been released on DvD but im keeping my ears and eyes peeled fr any info on its eventual release. I liked the movie because it also had other favorites of mine in it like Richard Egan and Neville Brand. Also, the other "war movie" he made was G.I. Blues and isnt a war movie. This one just recently got released on DvD as an "MoD" title. You can get it on the Warner Brothers website fro about $18.00.