There was a theory that they “Irish Traveler” minority were descendants of the original inhabitants of Ireland. It’s hard to believe that the Celtic migration didn’t encounter someone! The “Irish Travelers” have for want of a better term I’ll call it a “creole” called “Cant” or “Kant” (I’ve seen it spelled both ways!) which is theorized to be remnant of their native tongue heavily mixed with Irish & English.
I wonder how well that theory has held up? I wonder if there is any DNA evidence for it?