On brief review of given names circa 1870s-early 1900s in four areas in Ireland, (NW Clare and Cork/Muskerry in the south and near the Tyrone/Fermanagh border in the north) and to be used only as a general guideline:
Among the vast majority of the population the range of given names use in the 1800s was severely limited, parents often named their eldest children after grandparents and parents. A wider range of names were found in the Protestant community. Apart from some very localized names, i.e. "Cornelius," in south Munster, "Crohan" in the Caherdaniel area of the Iveragh Peninsula, "Sabina" in east Galway and north Roscommon, the anglicization of earlier Gaelic names was quite restrictive and John, Patrick, Michael, Mary and Bridget occur with almost unbelievable frequency in all parts of the country although Patrick, Michael and Bridget were names most often given to Catholic children.
In west Cork, children of today are more likely to be given names such as "Orla" or "Clara," or "Colm," rather than mainly local ones like "Conchubhar" or "Gobnait." In the north, Sean, Seamus and Mairead have became popular Catholic names.
Included in the "top ten" names found almost exclusively in the west Cork/Muskerry area (as opposed to the others) were inaccurate, anglicised versions of old Gaelic names: Daniel (Donal or Domhnall), Dennis (Donnchadh), Timothy (Tadhg), Jeremiah (Diarmuid), and Cornelius (Conchubhar).
Some names were common among both Protestant and Catholic communities in the 1890s and 1900s: John, Thomas, James, Margaret, Catherine, Ann, and Elizabeth. James had the edge in Catholic northern families, Elizabeth seen most often in Protestant northern families.
Edward was most often seen in Catholic families in the north. Joseph was found in both Tyrone/Fermanagh and West Clare as a Catholic name.
In areas in the south, such as West Clare and Co. Cork, Kathleen or Kitty/Katty was a popular name. Catherine was a very popular name in Cos. Tyrone/Fermanagh although found three times more often in the Catholic community than the Protestant.
In the northern areas such as Cos. Tyrone and Fermanagh, which contained a substantial Protestant majority, names such as Patrick, Michael, Bridget and Rose appear almost exclusively in Catholic families while names such as Robert, George, Samuel, Emily, Alice, Jane, and Jennifer were nearly absent from the Catholic community. Catherine appeared with some frequency in the Tyrone/Fermanagh area but three times more so in Catholic families. William was much more commonly found in the north than in the south.
The name Sarah was generally found in the north, and while present in both Protestant and Catholic families, it was more prominent in the former.
Of note, according to an article in "History of Ireland," naming one's first son William was a widespread practice a century ago in the north.
Martin, Austin and Stephen was often found in the West Clare region. Daniel was most often found in the Co. Cork, Muskerry area. Susan and Delia was found in West Clare. Nora was found in West Clare and Co. Cork/Muskerry in Protestant families. Hannah and Julia were popular names the in Co. Cork/Muskerry area.
Martha is found as a Protestant name in Cos. Tyrone and Fermanagh, and Agnes and Susanna were found in Catholic families as were Francis and Peter.
Ellen was found in all four areas in both Catholic and Protestant homes. Mary was the favorite name in all four areas in both Catholic and Protestant homes, as was Margaret. Anne was found in all four areas but most often in Both Catholic and Protestant families in the north.
There were significant differences between two southern Munster areas of Co. West Clare and the Cork/Muskerry area. Daniel, Jeremiah, Timothy, Cornelius and Dennis were seldom found in West Clare. Frederick was most often a Protestant name in the north.