Hi. I believe my first O'Brien to come to usa was Michael about 1837. He may have lived in NY and Mass. Eventually came to Tn and lived in Roane county about 1837. He married a Nancy Danley. Michael was a blacksmith. Some other first names are Hezekiah, Burrell and Earl (twins), Johnny, Alfred and Clyde Elmore (born 1919, my father. I believe all 6 were born in Davidson county, Nashville, Tn.