Re: Charles F. O'Conor - Baltimore MD - arrived 1867 died 1936
I searched the Irish Family History Foundation's database. It contains 12,000,000 surviving rcds for abt 65% of Irish counties. Rcds are increasingly sparse B4 1840, rare B4 1800. Caution - The IFHF charges a 5 euro fee per rcd to view the details.
Note 1 - Without a KNOWN parish, the chance of an ancestor's rcds NOT being in this database is AT LEAST 35%.
Note 2 - Only 1/2 of Co. Cork's rcds are in this database.
Note 3 - The RC church kept control over most parish rcds from Tipperary (north). These are ONLY available thru the Tipperary Family History Research center at a substantial fee (regardless of outcome).
Note 4 - Each parish's rcds have their own quirks and limitations, too many to enumerate individually.
You didn't do your homework in the U.S. You should check the U.S. Censuses for the relevant decades for his DOB. This info is also often on the naturalization papers. This forces me to guess that his DOB was 1847 +/- 4 yrs.
For Charles O'Connor B 1847 +/- 4 yrs somewhere in Ireland with the father's forename unknown, I found 44 B rcds - too many to summarize here. The naturalization papers are most likely to contain a placename of origin and exact DOB.
Google the foundation's name to lead you to this database. Register, opt to be notified as rcds are added and browse. Pls post your search results to my genform msg.
Hope this helps. Good luck.