I have done some research my self on familysearch.org and I have found that my Mack name goes all the way back to Co. Antrim, Northern Ireland, UK which near the city of Londonderry (derry). But The name originates in Scotland near Berwickshire. Which ties in perfectly because that area of Northern Ireland was predominately settled by the Scottish.
Mack comes to us from two main sources. 1) Scottish (Berwickshire) and Irish - from the Old Norse personal name Makkr, a form of Magnus (Old Irish Maccus). 2) North German, Dutch, and French (Alsace) - from the Germanic personal name Macco, Makko, a pet form of a compound name with the initial element mag, 'kinsman'. Source: Genealogy.familyeducation.com