My GGgrandfather, James Hugh Devlin, born ca. 1830, left Armagh in the mid 19th century to join the British army. His father, James was a farmer in Armagh. James Hugh married Ann Bittle in Pembroke Dock in 1861 and finally settled in east London where he died in early 1900s. I am just starting to follow this Irish line - could they be related to yours?