I think the key thing to remember is that the borders were a lot more fluid back then. So you could go to England or back to Scotland or to America or Back to Scotland. Barnett covered a lot of those grounds.

As a for instance, in my case, one chunk of my Barnett heritage is from Ireland, they are tied to Scotland as Barnett and Frayme.

So, until you can make the connections, don't get too hung up on the names.