It is a help when tracing your household history to know something about the origin of and advancement of Irish names and particularly how names have altered over the centuries.

Early times: In ancient Ireland the population was much smaller sized than today and the mass motion of people was uncommon. It was normal for that reason for a person to be known only by one name: Niall, Eoin, Art, etc. When there was nobody else in the locality with the same name then this was not an issue.

The Gaelic Clann system was well established and this offered individuals a typical identity with their people of the people and with the frequently shared location. This single name system started to break down during the l lth century as the population was growing and there was a requirement for a more methods of recognition. The solution was to embrace a prefix such as Mac (Mc is an abreviation) or Ó. Mac implies ‘kid of’ whilst Ó means ‘grand son of’. Mac surnames are normally of a much later date than Ó. The large bulk of Gaelic Irish surnames were developed during the eleventh and twelfth centuries.

It needs to be kept in mind that the Scottish Gaels were actually descendants of Gaelic emigrants to Scotland. The word ‘Scotus’ is Latin for ‘Irishman’. Scottish inhabitants who transferred to Ireland (and particularly Ulster) might already have been of Gaelic Irish descent.

Septs: The Clans ultimately separated into a number of unique septs or groups. These groups were headed by an original member of the clan and dominated a specific part of the countryside. It was not uncommon for septs from the same clan to be discovered in entirely various parts of the nation (O’Connor for instance) so it is necessary when investigating your roots to look for out the original part of the country that your ancestors came from as this may be an entirely different location from that where the ‘major’ sept was domicile

The sept system was an integral part of Gaelic society and endured and was even propagated by the Norman intruders. The system did not survive the English intrusion and colonisation of the seventeenth century nevertheless, and it ended up being a disadvantage to have a Gaelic sounding name.

Anglicization: The Penal laws that were imposed by the colonists attempted to completely rule over the Gaelic way of life. It is about this time then, that lots of Gaelic names changed to their Anglo equivalent or translation. This can trigger confusion as a number of the names were misinterpreted or misspelled. The name McEaneny for instance has a variety of variations consisting of McAneny and Bird (the Irish word for bird is éan). Mac an Thomáis was converted to Holmes, Mac Giolla Íosa to MacAleese, and so on. The conversion of names starting with Mac and Mc was a lot more challenging because the elimination of the M noise from the name often totally changed the sound of the name.

The revival of Gaelic awareness in the later eighteen hundreds saw numerous Irish families reassume the Mac, Mc, Ó or other Irish kind of their names although this was minimized in a number of cases depending upon the noise of the name (Kelly is still much more prevalent than O’Kelly, Murphy more widespread than O’Murphy, and so on)

Surnames today: There are many different origins for Irish names today however the vast bulk can be broken down into either of 3 categories: Gaelic Irish, Cambro-Norman, and finally Anglo-Irish.

The Table revealed here gives a listing of the 100 most typically names found in Ireland and their meanings. These information were put together from the Matheson report.

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