For background on how the map was made (and its flaws), see the relevant blog entry.
|MacElrath||Very rare: Tyrone. Ir. Mac Giolla Riabhaigh, riabhach, brindled or roan. See also Mac Areavey. SGA.|
|MacIlrath||Quite numerous: Antrim-Derry etc. Ir. Mac Giolla Riabhaigh, variant of Mac Areavey, q.v. See also Mac Ilwrath.|
DEDs where McIlrath and a second surname are found together