the flag representing the president of Ireland has a gold harp with a dark blue background – the color known as St. Patrick’s blue. The Irish presidential flag flies from the car of Ireland ...

The first Guinness labels featuring the now-iconic harp were printed in August of that year, according to "Guinness's Brewery in the Irish Economy 1759 - 1876" by Patrick Lynch and John Vaizey.

which is partly why a blue flag with a harp is associated with the Irish President. HISTORY.com says green is not a color that has much of an actual connection to St. Patrick but rather originated ...