Origins of the name

There are two origins of the Kennedy surname: one Scottish and the other Irish. The most commonly known Kennedy family is the Irish one made famous by the late U.S. President John F. Kennedy, whose ancestors came from County Wexford.



Irish Kennedy

The Irish Kennedys takes their name from Kennedy, the nephew of High-King Brian Boru (1002-1014). Kennedy is an anglicised form of the Irish “Ó Cinnéide”. The name Cinnéide first used by Brian Boru’s father Cennétig mac Lorcáin, King of Thomond, in the tenth century AD. (Brian Boru was an Ard Rí or High King of Ireland). His grandson became known as Ó Cinnéide which is Irish for grandson of Cinnéide. The Kennedys did not descend directly from Brian Boru, but from his brother.

Cinnéide is Irish Gaelic for helmeted head. The original Cinnéide was apparently the first Irishman to wear a helmet in battle against the vikings. This is remembered in the Kennedy coat of arms which features three helmets.

This Irish Kennedys were the left hand of the powerful Dál gCais Tribe of Thomond, headed by the O’Briens. They resided in far eastern Clare, northern Limerick, Mayo, and northern Tipperary in an area called Ormond.

Two groups of Kennedys occupy Ireland: One is Irish and the other is Scots. Therefore, many confuse the two families and the lands they are from.



Origin of the Irish Kennedys

The Irish Kennedys were a member of the Dál gCais or “Dalcassian sept.” Originally seated in Glemor, near Killaloe in Co. Clare, they migrated across the river Shannon to Ormond in Co. Tipperary following pressure from other septs in the region (mainly the O’Briens and the McNamaras).They soon grew in power to become Lords of Ormond from the 11th - 16th centuries. The Annals of the Four Masters described them in 1300 to be “the undisputed Lords of Ormond“. Placenames such as Coolkennedy and Garrykennedy in Upper Ormond and Killokennedy in Thomond are indicative of their longstanding presence in the region.

The sept split into three branches, the chiefs of which were referred to by their hair colours: don (brown), fionn (blond), and rua (red). St Ruadhan of Lorrha was the special protector of the Kennedys of Ormond. Around 1600, a branch of the sept migrated to Co. Antrim where many Kennedys are still found today, although some may be of Scottish origin.

According to Daithi O’hOgain (Associate Professor at University College Dublin), some Irish Kennedys are directly descended from Brian Boru: ‘The name Cinneide also continued in the direct O’Brien line. For instance, a branch of the family descended from King Donnchadh, son of Brian Boru, settled in Aherloe in south Tipperary, one section of which had the name Cinneide as a surname. Another Cinneide O’Briain, grandson of the same Donnchadh, was a strong opponent of his kinsman, King Toirdhealbhach, and on this account he was assisted by the Connacht king, Aedh O’Ruairc of Breffny, to set up a kingdom of his own on the Meath-Cavan border. This little kingdom was broken up by Toirdhealbhach’s army in 1080, and Cinneide O’Briain himself was slain in 1084 at the Battle of Monecronock, near Leixlip in Count Kildare. The connection with the O’Rourkes of Breffny did not end, however, for some people bearing the name Cinneide settled in that area of County Leitrim. These were known by the synonym Muimhneach (‘Munster-man’), which is anglicised as the surnames Mimnagh and Minnagh.’ (O’hOgain D. (2003) ‘Kennedy O’Cinneide’, Gill & Macmillan, Dublin pp40-1).



Scottish Kennedy

Their home territory is in southwestern Scotland, in Ayrshire, where they were a power house. Originally they came from the western isles and are of Celtic-Norse stock. In the fifteenth century, one Ulric Kennedy fled Ayrshire to the highlands for refuge where he was granted protection under the Chief of Clan Cameron. From this Highland branch, Kennedys settled on the Isle of Skye. A branch also was established in northeast Scotland, at Aberdeen.

To add to the confusion, there are the Kennedys of Northern Ireland. The majority of the Kennedys who settled in Northern Ireland are of Scottish origin from the territories of Galloway and Ayr just across the Irish Sea some 20 miles away. Many Scottish Kennedys were planters in Ulster (the province of Northern Ireland), and many Scots went to Dublin and mingled with the Irish clan. Because of this confusion, the Scottish Chief of Kennedy is willing to recognize all Kennedys as part of the clan/family.



Origin of the clan

The Scottish Kennedy clan originated in Carrick in Ayrshire. The clan was one branch of the Celtic Lords of Galloway.



Wars of Scottish Independence

The Clan Kennedy supported King Robert I of Scotland before and through the Wars of Scottish Independence and were rewarded. Around 1360 John Kennedy became owner of lands at Cassillis and in 1457 his descendant, Gilbert, was created Lord Kennedy. Gilbert’s younger brother James was Bishop of St Andrews and founder of Scotland’s first university, the University of St Andrews.



Anglo Scottish wars

During the Anglo-Scottish Wars the Clan Kennedy led by their Chief who was the 1st Earl of Cassillis fought at the Battle of Flodden Field in 1513 where the Chief was slain.



17th & 18th centuries

The death warrant of Scotland’s first Protestant martyr, Patrick Hamilton, was signed, under pressure, by the 3rd Earl, Gilbert, when twelve years old. He was poisoned at Dieppe and the Earldom went to another Gilbert, celebrated for roasting the Abbot of Crossraguel slowly over a fire to gain his land. The Abbot was saved by the Kennedys of Bargany but not before being horribly crippled.

In 1775 the 10th Earl of Cassillis was David, who commissioned Robert Adam to build the stunning Culzean Castle. The half gothic, half classical masterpiece looks across the Firth of Clyde to the Ailsa Craig and was offered for use as a retreat to Eisenhower in gratitude for his war achievements.



Modern day presence

Kennedy is the 16th most common surname in Ireland with ~20,000 bearers, in the USA it is the 137th most common surname with ~185,000 bearers, in England & Wales it is the 168th most common surname, and in Scotland it is the 58th most common surname. In the USA some of most famous Kennedys belong to the Kennedy Family.






In Ireland

The Kennedys’ castles in Ireland were all located near Nenagh in North Tipperary. The following castles were built by, or held by the Kennedys:

      Ballintotty Castle

      Dromineer Castle

      Garrykennedy Castle

      Nenagh Castle

      Lackeen Castle



In Scotland

      Greenan Castle in Ayr in south-west Scotland.

      Dunure Castle in South Ayrshire, Scotland.



Scottish Kennedy Family Tree Base

Here is the base of the family tree:

1 John Kennedy of Dunure and Cassillis M Heiress of the Carrick Earls

1.1 Sir Gilbert

1.1.1 James M Princess Mary (2nd daughter of Robert III) Gilbert (Became Lord Kennedy in about 1457)

1.1.1.x James Kennedy (He served as High Chancellor of Scotland and was Bishop of Dunkeld, and later Archbishop of St Andrews. At St Andrews he founded St. Salvator’s College in 1455 and is considered one of the founders of the University of St Andrews) Hugh Kennedy of Ardstinchar (Worked for the scottish mercenaries and fought with Joan of Arc at the siege of Orly) Sir David (Third lord of Kennedy, created Earl of Cassilis in 1509)

The tenth Kennedy Earl commissioned Robert Adam to build the Culzean Castle, which became the seat of the Kennedy Clan.

The twelfth Kennedy Earl was created Marquess of Ailsa



Clan profile



Gaelic names

      MacUalraig (Surname)


      Ceannaideach (Singular)

      Clann ‘icUalraig (Collective)




      Irish: Sable three helmets in profile Argent

      Scottish: Argent, a chevron Gules between three cross crosslets fichée Sable, all within a double tressure flory counterflory Gules.


The Arms of the Marquis of Ailsa

Argent a chevron Gules between three cross crosslets fitchee Sable within a double tressure flory counter flory of the second.




Scottish chief

      The Most Hon. Archibald Angus Charles Kennedy, 8th Marquess of Ailsa



Scottish septs of Clan Kennedy











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