Mahaffey Family History and Genealogy. PDF eBook English 15.6 MB. The Clan Mahaffey originally came from Scotland, and migrated to Northern Ireland along with thousands of others. The book contains the brief history of this migration, and that Charles Mahaffey, progenitor of the Cumberland Valley Mahaffeys, immigrated from Northern Ireland to New England prior to June, 1753. His descendants then migrated into the frontiers of Ohio, and the Northwest Territory which became Michigan. Family lore dates back to the year 1600 with numerous rare ancestral photographs. Thousands of Mahaffeys listed. A great resource for the Mahaffey family genealogist!