Baron Offaly is in Baron Ireland.
In October 1578 Gerald Fitzgerald Baron Offaly [aged 18] and Catherine Knollys Baroness Offaly [aged 18] were married. She by marriage Baroness Offaly. He the son of Gerald "Wizard Earl" Fitzgerald 11th Earl of Kildare [aged 53] and Mabel Browne Countess Kildare [aged 42]. They were sixth cousins.
Gerald Fitzgerald Baron Offaly was created 1st Baron Offaly.