When we started the Byrne/Burns/Beirne project, most with those surnames assumed they were descendant from the Clan O'Byrne of Leinster, but we soon discovered three major divisions into Leinster, Northwest (M222), and what we called Monaghan. We then discovered that a number of Monaghans differed from the neighbors that they thought were related--and are M222. We had no special tag for the major Monaghan group until Joe Donohoe, with his Breifne project, devised Airghialla-1 and Airghialla-2 modals. So today, we are able to divide our previously-called Monaghans into three quite distinct groups. One clearly is Northwest Irish (n-12), as identified by M222. It is Lineage IId on www.worldfamilies.net/surnames/byrne/results and seems to be linked to the Reillys. The second and largest (n-26) is Airghialla-2, and is identified by L513. It is linked to the McGuires and is our Lineage III. The third and smallest (n-2) seems to fit the Airghialla-1 modal, but I have no info on its origins. It is our Lineage XII. Paul