The Irish clan system is the oldest reliable example of that type of community. Based on ancestry, it could be called the original lineage society! In its purest form, the clan system only existed in Ireland and Scotland; however, variations of the theme can be found in nearly every society and culture throughout human history. The clan system demonstrates just how important genealogy was to the Irish, and a study of it can greatly expand one’s understanding of the lives and times of one’s Irish ancestors.

Irish society organized into clans in ancient times, long before people had surnames. The Irish clan system was based on communities that were organized around a common bloodline and ancestry, usually with one powerful clan member taking the position of leader. Naturally, as time progressed, some clans in Ireland became larger and more powerful than others. Eventually, there were 4 or 5 very large clans on the Emerald Isle, and these eventually became known as royal clans. The title of High King of Ireland (which was basically a symbolic position) was rotated among the leaders of the royal clans. The leaders of the royals clans were known as Chiefs, while the leaders of smaller clans that were dependent on or protected by the royal clans were called Chieftans. O’Connor, O’Brien, O’Neill, and MacMorrough were some of the first royal clans to emerge.

Chiefs and Cheiftans were appointed by the other members of their clans, and were charged with maintaining and protecting the clan and its belongings (including land). Irish society was based entirely on the clan system until the 17th century.

It is also through the Irish clan system that surnames emerged. In ancient times, people in Ireland would refer to themselves as “son of” or “grandson of” their fathers or grandfathers. As the clan system took shape and leaders emerged, those leaders typically took on the name of one of their powerful ancestors and became known as “son of” or “grandson of” that person. The familiar “O’ ” in front of many Irish surnames today literally translates into “son of” or “grandson of.” The leader would then forego the use of a first name, and just be referred to as “son of” or “grandson of” the ancestor who he chose for his name. The other people in his clan would use their leader’s new name as their surname. So, for example, if a leader became known as “son of Douglas” (which became “O’Douglas”), then O’Douglas would become the surname of everyone in the clan.

The end of the Irish clan system came about in the early 17th century, when the ruling Tudor monarchs in England established control there. England disarmed and disbanded the clans and overthrew their leaders, establishing a centralized government there for the first time. Despite the official loss of their clans, the people of Ireland never let go of the spirit of the clan system, however, and most Irish men and women could tell you their clan even a century or more after the clans were gone. In the 1940’s, the Chief Herald of Ireland drew up a list of more than 240 ancient Irish clans, and those clans began formally re-organizing in the later part of the 20th century, with elected Chieftans once again.

Today, The Clans of Ireland, an independent group, maintains an official Register of Clans, and is considered today to be the foremost authority on Irish clans in the world. The re-emergence of the clan system in Ireland just goes to show you can never keep the Irish down, and the spirit of their heritage that lives in their hearts is as strong now as it was when the clans first formed long ago.