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Irish genealogy website directory.
www.rootsweb.ancestry.com/~irlkik/ksurname.htm
Description:
A study of 1890 Irish birth registrations for the county of Kilkenny indicate Brennan as the most common surname with 2195 individuals of this name, followed by Walsh with 2016, Murphy with 1568, Ryan with 1523, Carroll with 1120, Byrne and Butler with 986 each, Maher with 941, Dunne with 896, Phelan with 805; Kelly, Neill, Power and Purcell each with 762, and Delaney and Dowling with 727 each.