The harp, which serves as the emblem of Guinness, is based on a famous 14th century Irish harp known as the "O'Neill" or "Brian Boru" harp, which is now preserved in the Library of Trinity College Dublin.
The harp device has been synonymous with Guinness since 1862, and according to some calendars it dates back to today April 5, when it was used as a symbol on the first bottle label for Guinness. It was registered as a Guinness company trademark in 1876.
The harp is also the official national emblem of the Republic of Ireland and can be found on the Republic's coinage.
However, there is a difference between the Irish government harp and the Guinness harp. As Guinness had trademarked the harp symbol in 1876, the Irish Free State Government of 1922 had to turn the official government harp the other way aroundso as it could be differentiated from the trademarked Guinness harp.
The distinguishing feature between the two harps is that the Guinness Harp always appears with its straight edge (the sound board) to the left, and the government harp is always shown with its straight edge to the right.
It is because of the harp trademark that the Guinness company named its first lager ‘Harp’ in 1960. The harp is one of three elements that make up the Guinness livery. The other two elements are “Guinness” (the word) and Arthur Guinness’s famous signature.
There have been a number of changes to the design of the harp device over the years including a reduction in the number of strings shown. The current harp was introduced in 2005 when a new brand livery was launched.
The famous Downhill Harp, dating back to 1702, which is on display in the advertising gallery in Guinness Storehouse, was purchased by Guinness in 1963, to ensure its continued preservation.
The harp was made by Cormac O’Kelly of Ballinascreen and played by the blind harpist, Hempson (or O’Hampsey) in the 18th century. Hempson played in the traditional style, plucking the strings with his long fingernails. At 97, he was the oldest harpist at the Belfast Harp Festival of 1792, although he is perhaps most famous for his concert for Prince Charles Edward Stuart, or ‘Bonnie Prince Charlie’, in 1745.
The harp bears the inscription:
“In the time of Noah I was green,
Since his flood I had not been seen,
Until Seventeen hundred and two I was found By Cormac O Kelly underground:
He raised me up to that degree
That Queen of Musick you may call me.”