I have a really older than dirt Irish surname myself, and find the changes of names very interesting. Sometimes they mean the same in two different kinds of gaelic.
My G-G-Grandmother was a Graham , yes the Montrose kind , who lived in a cottage on the road up to Stirling Castile . She was a “housekeeper” there . She came to what is now Ayr, Ontario , where she worked for an uncle who owned the Black Horse Inn which was located on what is locally today called Black Horse Hill. , north of the 401 highway exit to Ayr. The uncle happened to own two black horses. There she met G-G-Grandfather , the local butcher.
My mother’s father served under Currie when he led the 1st Canadian Division in 1916-17. Grandfather was RCHA .Gassed at the Somme he later fought in Russia 1918-19 with the Canadian Artillery , 16th Brigade , against the Bolsheviks . He tried to enlist in “39” and gave his nationality as Irish. Never mind his family had been in Canada for over 150 years and he was the 4th generation to be born here. His only son , as a 20 year old , joined RCAF in 1941 and listed his nationality as Canadian . He was killed with the rest of his Lancaster bomber crew, G for George , June 1943 , on his 27th mission.
Look under research notes :
http://www.canadiangreatwarproject.com/searches/soldierDetail.asp?ID=64384