Many of the males on my father's side of the family (That'd be the Scots side) have middle names that were last names of female branches in the family tree. My father, grandfather and I had no middle names in a tradition dating back time back way back. Family lore had it that the middle name convention was an old Scots convention that was banned after the '45 to muddle evidence of clan alliances. I'd always WAGged that the habit of having family names as given names (e.g., Craig, Scott, Murray) came about as a result of the mixing of this middle name convention with the continental practice of having a saint's name as a middle name.