My ancestor's records just say 'Ireland'. How do I find the county?

This is the normal problem, not a dead end. American records rarely volunteered a county, so work the ones that might: a naturalization petition after 1906 gives a birthplace; an American death certificate names parents and sometimes a birthplace; a gravestone, especially in an Irish parish cemetery in America, often names the county; an obituary in a local or Irish American newspaper can name the parish. Then widen out: emigrants travelled in clusters, so trace the witnesses, godparents and neighbours, whose records may name the place yours does not. In the Irish records, a distinctive surname can narrow the field: our surname map shows where a name sat in 1890, and Griffith's Valuation can test a candidate county quickly. Expect the answer to come from three records agreeing, not one.

Useful pages: Irish in USA · The Irish surnames map · Trace your Irish roots · Coming home · Irish around the world

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