http://www.theatlanticcities.com/politics/2012/08/mapping-citys-surnames/2812/
The reader should be mindful that, owing to migration over centuries, even in the heart of old Londinium the surname Smith can quite often denote an Irish or Scots origin, being a name frequently derived from the Gaelic patronymic Mac Gobhann, meaning “son of the smith”.
To be sure, Smith is an English name as well, but it is the most common surname in Scotland (followed by Brown, Wilson, Campbell, and Stewart in the Top 5). Smith is commonly found in Ireland as well, sometimes being another form of that recurring “MacGowan” (Mac Gabhann) occupational name, and sometimes representing the old English Smith qua Smith families who had settled in Ireland. ~Q~
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