John O'Hart

John Hart, the Irish genealogists, believed that all Irish descend from the mythical Milesius, himself a descendant of Adam.

Wikipedia says this:

"According to O'Hart's account, Milesius had four sons, Heber, Ir, Heremon, and Amergin, who were involved, along with their uncle Ithe, in the invasion of ancient Ireland; Milesius, himself, had died during the planning. Because Amergin died during the invasion, he died without issue. It is from the four other invaders--Heber, Ir, Heremon, and Ithe--that the Irish are alleged to descend. These. according to O'Hart, are the four lines from which all true Irish descend."

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