Can you guess which states have populations with the greatest percentage of Irish ancestry? Nine states have more than 17% "Irishnicity": Montana, Iowa, Pennsylvania, Vermont, New Hampshire, Maine, Massachusetts, Connecticut and Rhode Island. IrishCentral's report can be read at www.irishcentral.com/news/nine-us-states-have-more-irish-percentage

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The article is based on census demographics found in the book Ancestry and Ethnicity in America. The U.S. census shows over 35 million Americans claiming Irish roots and an additional 5 million claiming Ulster Irish descendancy. The Irish numbers are second only to German-Americans.