A complete and well-researched history of the O'Sullivan clan, the most senior branch of the royal family of Ireland, is available.
The Personal Arms of The O'Sullivan Mor
The Personal Arms of The O'Sullivan MacCragh
The Personal Arms of The O'Sullivan Beare
"While kilts and tartans, as we know of them today, were a nineteenth century development, they remain effective devices with which modern clan organizations can promote unity and identity among their members. Facebook and other social mediums were not available to our ancestors either, but we still employ them to establish and maintain a clan community. Absolute historical purism would preclude the existence of any modern clan societies, an end which I suspect some purists actually desire. As to the Irish being descended from kings, it is true that there were 'noble' Gaelic families and 'common' Gaelic families and not everyone with a certain Irish surname can claim, with certainty, that their ancestors were of the ruling class. However, the Irish 'king' was a true form of the concept, representing 'kin' or family. The Irish kings were chosen from among their people. All of them shared blood with their clan. While only certain individuals were known as 'Chiefs of the Name' and were afforded the Norman conceit of heraldic achievements, their only claim to nobility was their esteemed position among their extended family or clan. So, in the case of the Irish, every member of the clan, in a way, can claim a valid association with the 'clan shield'."