Yitzhak HaLevi Herzog

Yitzhak HaLevi Herzog, also known as Isaac Herzog, was the first Chief Rabbi of the Republic of Ireland and, later, of the British mandate in Palestine and Israel, once formed.

An Irish Jew, Herzog was a compatriot of Eamon DeValera of the Irish independence movement.

Herzog is most famous for his re-discovery of Techelet, the type of blue dye that is used for the making of Tzitzit.

Herzog's son, Chaim Herzog, was later president of Israel (and, incidentally, the only president of Israel who was born in Ireland).