The harp was adopted as the emblem of the Irish Free State when it separated from the United Kingdom in 1922.

Several variants of the arms of Ireland exist, including a heraldic badge and an infrequently used crest and torse.

The Wijnbergen Roll, a French roll of arms dating from c. 1280 and preserved in The Hague, Netherlands, attributed "D'azure a la harpe d'or" (English: Blue with a harp of gold) to the King of Ireland ("le Roi d'Irlande").

[5] Triangular devices appeared on medieval Irish coinage by kings John and Edward I in the 12th and 13th centuries.

[6] The idea of a harp being the arms of Ireland may have originated as a reference to a fictional character, le roi d'irelande, in the courtly legend cycle of Tristan.

Alternatively, it may have derived from a celebrated 13th century bardic poem, Tabhroidh Chugam Cruit mo Riogh, dedicated to Donnchadh Cairbreach O'Briain (d. 1242), a Gaelic King of Thomond.

[7] Whatever its origins, the harp was adopted as the symbol of the new Kingdom of Ireland, established by Henry VIII, in 1541.

It appears on the arms of countries with historical links to Ireland or the United Kingdom, such as Montserrat and Canada.

In 1984, exemplars of the modern design, approved by the Chief Herald, were registered by the Government of Ireland with the World Intellectual Property Organization under Article 6ter of the Paris Convention, which relates to state emblems.

While the Attorney General's office felt that right-facing images should also be registered, patent agents advised this might be interfere with Guinness Brewery's use of such harps in its logo since the 1870s.

[7][13][14] The association of these arms with Ireland is likely to have originated with Irish magnates (both Norman and Gaelic) who fought in Edward I's Scottish wars at the turn of the 14th century.

Strictly speaking, following the Norman invasion of the 12th century, Ireland was a feudal possession of the Pope under the overlordship of the English monarch.

Thus, at the funeral cortège of Elizabeth I in 1603 depicted in a manuscript at the British Library, the Earl of Clanrickarde is shown carrying the banner of Ireland just as in the Wijnbergen Roll.

The variant apparently used as the arms of Ireland were of a majesty on a sable (black) background instead of an azure (blue) field.

Metcalfe's design became the model for future official interpretations of the harp as an emblem of the state.

During the 17th century, it became common to depict the harp with a woman's head and breasts, like a ship's figurehead, as the pillar.

It is not necessary to show a full complement of thirty strings, provided that the numbers do not fall below nine (notwithstanding the illustration to the left).

Unlike Scotland, Ireland did not reserve the right to bear a distinct coat of arms within the United Kingdom.

For example, during the late Tudor period, depictions of the arms appeared accompanied by a dragon and a lion, representing Wales and England.

The earliest-known record of the green flag is attributed to Eoghan Ruadh Ó Néill, a 17th-century exile and soldier in the Irish brigade of the Spanish army.

His ship, the St. Francis, is recorded as flying from her mast top "the Irish harp in a green field, in a flag" as she lay at anchor at Dunkirk en route to Ireland.

For example, the arms of the Genealogical Office, which is headed by the Chief Herald of Ireland, are the four provinces shown quartered beneath a chief Gules, charged with a Tudor Portcullis Or between two Scrolls Argent (a red band with a gold Tudor portcullis between two silver scrolls).

[7] Finally, Connacht's arms are blazoned Party Per Pale Argent and Azure, in the first an eagle dimidiated and displayed Sable in the second issuant from the partition an arm embowed and vested, the hand holding a sword erect, all Argent.