Depending on his date of muster he could of been conscripted more or less drafted .Just a thought. ..My GGGrandfather was an Irish national in the 6LA.Inf..He stated when asked to sign the Oath of Allegiance to the U.S. he jioned the Confederate Army to secured employment(New Orleans blockaded there was no work)and to avoid conscription.He recieved fifty dollars bounty that he would not of recieved if conscripted.Pvt.Daniel Riordan #2 Co.F.. Even though he didn't have a political bone in his body he too was captured three times and returned to his regiment except the last when he was held till after the war was over.I would advise you to read "Irish Rebels,Confederate Tigers"while a history of the regiment it also has a prelude to what New Orleans was like prior.Liverpool was a destination for cotton ships and the return trip was said to need balast or Irish ,Irish paid.Did your kin come from Liverpool?