Guinness converted its Dundalk brewery into a lager production plant with the guidance of Dr. Herman Muender, a German brewer.

[1] Various names were considered for the brand before Harp was chosen, including Atlas, Cresta, and Dolphin.

[3] In 1961, a consortium of brewers, Courage, Scottish & Newcastle, Bass, Mitchells & Butlers and Guinness, grouped together as Harp Lager Ltd. to brew and market the beer.

The last Harp from Great Northern was brewed in 2013, after which production moved to St James's Gate Brewery, Dublin.

In North America, exports are labelled "imported from Ireland" and are brewed at Guinness' St. James Gate brewery in Dublin.