WALSH OF COUNTY GALWAY ANCESTRY

I'm endeavoring to confirm that Owen Walsh ( refer to as Owen, Sr. )  baptized 10 July 1848 in St. Nicholas Combined, Galway is my great grandfather and if not,  then find exactly who is my great grandfather.

Here is my story:

Although my surname is Kealy, in fact, my paternal line is Walsh.. My grandmother ( Anne Kealy ) gave birth out of wedlock with Owen Walsh, Jr... My father's birth certificate shows his name as Eugene Kealy born 1913 in Brookly, N.Y. - thus my surname.

Owen, Jr. was born in Brooklyn, New York 23 December 1879. His father is believed to be Owen, Sr. in union with Delia Ellen " Bridget " Burke, who was likely born in Ireland in or near Dublin.

Owen, Sr. immigrated to New York about 1870.. 

I'm in contact with several of my Walsh, second cousins being descendants of Owen, Jr. siblings - they being in birth order William, Mary Ellen,` Owen and Patrick. All of us Walsh second cousins are unable so far to confirm our great grandfather. We have some documents, such as, Owen, Sr's death certificate, but it does not contain any helpful information.

In hopes of finding solid DNA Walsh matches either living or born in Ireland I entered 5 DNA testing databases.. So far, no solid DNA clues have surfaced but is does seem clear my Walsh ancestors originated in County Galway.. Recently I upgraded my Y DNA at FTDNA to Big Y 700 and are now awaiting the results.

Any suggestions on how I can best find some good clues or hints to advance my quest will be greatly appreciated..

Thank you,

Arthur Kealy

Update to the above message..

Im not sure which townland  to seach for records as there are about 16 Townlands within St. Nicholas Parish.. Assuming I got the right Owen Walsh the Church Baptism record states ST. NICHOLAS COMBINED N&E per rootsireland information, but I have no idea of which Townland or Church to search for family information.

So far I have very weak hints per various dna matches that have information which include Castlegar, Oughterard, Moycullen and Barna.. How do I find the right Townland and Church to search?

Thank you,

Arthur Kealy