Surnames in the British Isles became more prevalent after the Norman invasions starting in the 12th century. Many of the modern surnames from Scotland and Ireland are anglicized versions of old and middle Gaelic or old Norse personal names. The most common personal names for our surname group were Áleifr or Óláfr from old Norse and Olaf from Scottish and Irish Gaelic. Many descendants preceded their names with Mac, Mc, M' and O’, abbreviations for “son of”. The exact spellings of surnames appear to be due more to the person who recorded the name or their location than the particular surname itself. My McAuley family line was spelled 12 different ways going back to 1635. A partial list of surnames are listed on the Background tab. There are multiple separate branches of Irish and Scot, Nordic and Celtic origins with many of the branches interconnected over the centuries. If you are serious about finding your direct male ancestor’s roots, you need to take the BigY DNA test. BigY DNA testing has confirmed some of the separate branches of family lines and their origins. Additional information on these and newly identified branches are being developed as more BIGY testers results are generated. As additional information becomes available, it will be posted in the Results Section (see the tab above). If you join our project, please include the name, birth and/or death date and location of your most distant known male ancestor on the straight male line.