Irish Heraldry

A distinctive feature of Irish heraldry is acceptance of the idea of sept arms, which belong to descendants, not necessarily of a determinate individual, but of an Irish sept, the chieftain of which, under Irish law, was not necessarily a son of the previous chieftain but could be any member of the sept whose grandfather had held the position of chieftain. A member of the particular sept has the right to the arms of that sept, a right that on the contrary does not belong to people of the same surname who belong to a different sept. For example, a person from the O'Kelly sept of Ui Máine may display the arms of that sept, but a Kelly of the Meath or Kilkenny septs cannot.

Proponents of English heraldry and those who hold a documented right to arms see sept arms as controversial, but the Irish Genealogical Office (previously known as the Office of Arms) "holds that any member of a sept may display the arms of that sept (as distinct from personally 'bearing' the arms, as on stationery, silver, or other such use, [for] only the grantee and his descendants may 'bear' the arms)". Edward McLysaght, the first Chief Herald of Ireland after independence and the author of several works on Irish families, introduced this distinction.

Even after the introduction of English heraldry into Ireland and the setting up of arrangements for regulating it, the arms registered were undifferentiated, that is, they show no signs of the practice of changing a tincture or adding some symbol to personalize those of a particular individual. Brennan concludes that, rather than being the property of an individual, the arms belonged either to the sept as a whole or to the chief or to all members of the ruling élite in the sept. The hundreds of people claiming the right to arms indicate, Brennan says, either that they had used those arms for some time, or that the arms did not belong personally to the chief or that they were obviously based on the ancient clan system, so that the chief could not complain of their use by others.