Hmmmmmm, Daniel - - I must disagree with some of your answers.
Some of the information given is incorrect.Scots-Irish is an American term for describing the Ulster Scots (mainly Lowland Scots sent to Ireland during the Plantation period and who subsequently migrated on to America).
Also, what is your source for stating that "There was a time after the Revolutionary War, when Scots were not allowed entry into the country" ??As a History major, I have never run across any Scottish probitions by the US.Did you mean that they could not leave Scotland, or that they could not enter the new USA?
From the book “Mac, Mc, and O Names in Ireland, Scotland, & America" by Michael C. OLaughlin
"From the Intro to this work here is a passage from the introduction of this work; Mac names originate in Scotland and Ireland. The 'O' names, which appeared first by many accounts, is a name considered exclusively Irish. Nearly all old Irish surnames were originally prefixed with Mac or 'O'. They were such attractive additions to a name that some families settling in Ireland from abroad took a name with a Mac prefix. This included the Vikings & the Normans! Some old Irish families would drop the Mac or 'O' during certain periods of turmoil.....so the plot thickens when trying to determine exactly what your name might have been spelled like then.
One fact needs to be recognized immediately. There is no difference between Mac, Mc, and M'. You cannot say one form is Scottish and one is Irish. It becomes obvious that Mc and M' are both merely shortened forms of Mac, which is the originally Gaelic form that has come to stand for 'descendant of'. Originally the 'Mac' meant 'son of', and the 'O' stood for 'grandson of'. Today both simply mean 'descendant of', or perhaps more generally in some cases 'follower of'. (The latter is more often ascribed to 'Gil' names like Gilmartin or Kilmartin, coming from the Gaelic 'giolla'). Census records often use the shortened forms of Mac, it simply saved time and space, as in the census records shown in this book."