Kathleen is the early Irish import version that came between Katherine and Kaitlin, and which hasn't been used in so long it's almost beginning to sound fresh again. It was a surprise pick by one of the hip Dixie Chicks, Martie Maguire. But on the US popularity list, it's in decline, plummeting more than 200 places since 2010.
From the eighteenth century, Kathleen Ni Houlihan appears in Irish songs as a symbol of Ireland, representing its struggle for independence.
Kathy Griffin and Kate Walsh were born Kathleen, and it's J.K. Rowling's middle name. JFK's sister Kathleen was known as Kick.