Dan Rooney will resign as U.S. ambassador to Ireland Friday after more than three years serving as President Barack Obama's top diplomat in Dublin.
The resignation, which has been expected for some time, will allow the 80-year-old Steelers chairman emeritus to return home to Pittsburgh with wife Patricia after serving as ambassador since July 2009. Mr. Rooney was a vocal supporter of Barack Obama during his 2008 presidential run, which led to his appointment, but he had been involved in Irish causes for decades, co-founding the American Ireland Fund with former H.J. Heinz Co. president Tony O'Reilly in 1976.