If you are searching for Irish ancestors, you will be interested in an article published in the IrishCentral web site. It starts off with:
“Genealogist Barry Griffin used data from the 1901 and 1911 Irish censuses to plot out surnames on the map of Ireland
“More than 6,000 Irish surnames are included on a website compiled by genealogist Barry Griffin that lets users explore where in Ireland the surname was concentrated.
“Using data compiled from Ireland’s 1901 and 1911 censuses, Griffin has pieced together information on thousands of Irish surnames.
“Where in Ireland each surname was most concentrated and the popularity of each surname are featured on Griffin’s site. His database is sure to be a worthy tool for those researching their Irish genealogy.”
You can read the full article at: https://www.irishcentral.com/roots/irish-surname-maps