Table of Contents

Two Matching Sets of Seven Names

The identification of Brian Boru DNA rests upon the similarity between a set of seven names in the ancient genealogy of Brian Boru and a set of seven names among 88 of 160 testers with R-FGC5659 Y-DNA.

Many people with Brian Boru DNA do not have historical surnames. The major names are: Kelly, Lindsey, Littrell, and Morrissey. Brian Boru DNA has not yet been found for some historical Brian Boru names.

Abridged Brian Boru Big Y SNP Tree

Foreword

My interest in FGC5659 Brian Boru DNA and L226 Cas DNA stems from the marriage of our son into an O'Brien family. Their family genealogist Maureen O'Brien traces their heritage back to Michael O'Brien, who was born in Doneraile in 1815. Doneraile is in County Cork, about 90 miles south of Dromoland Castle in County Clare, the home of Conor Myles John O'Brien who traces his ancestry back to Brian Boru. Maureen's father Leo O'Brien, kit 197598, has this DNA. He matches men with a set of surnames that correspond to a set of surnames descended from the Dalcassian tribe, which is traced back to 3rd century Ireland. The most illustrious Dalcassian was Brian Boru, Brian Bóruma mac Cennétig, who was born around 943 AD in County Clare, Ireland. He was killed at the Battle of Clontarf on April 23, 1014.

In April 2006, Ken Nordtvedt identified a unique DNA of a group of testers with Irish ancestry centred on the counties of Clare, Limerick and Tipperary. One of the people who had this DNA was Dennis Wright. It was the third unique Irish DNA to be identified, so Dennis called it Irish Type III DNA. In December 2006, he started The Irish Type III Website.

In Spring 2009, Dennis Wright had a paper published in the Journal of Genetic Genealogy entitled "A Set of Distinctive Marker Values Defines a Y-STR Signature for Gaelic Dalcassian Families" that concluded the following.

Analysis of 25-marker short tandem repeat haplotypes in the Ysearch database reveals a distinctive Y-DNA signature that peaks in frequency in the Irish counties of Tipperary, Clare and Limerick. These counties were the hereditary homelands of the Dál gCais families, also called Dalcassian, septs descended from Cas, born CE 347, sixth in descent from Cormac Cas, King of Munster. Dalcassian surnames are more strongly represented with this signature than other surnames.

Conor Myles John O'Brien traces his ancestry 31 generations back to Brian Boru. He tested his Y-DNA at Family Tree DNA in 2004. His kit is 29355. He eventually confirmed that he had the FGC5659 SNP of Brian Boru.

The FGC5659 SNP of Brian Boru was named by Full Genomes Corporation in 2013. In February 2021, over 50 O'Brien testers were included among the testers with the FGC5659 SNP of Brian Boru, including Leo O'Brien, kit 197598.

Table of Contents     

Brian Boru (941-1014)

The Clare County Library has provided the following description of Brian Boru (c. 940-1014).

Brian Boru was born around 943, the youngest of two sons of Cennedig, head of Dal Cais, one of the royal free tribes of Munster. Brian grew up during the worst days of tyranny when the Dalcassians had been driven in to the present county of Clare. Brian’s brother, Mahon, being the eldest, succeeded Cennedig as chief of the Dalcassians. Being hemmed into Clare by the Norse Leader, Ivar of Limerick, Mahon was willing to accept terms but Brian, seeing almost all of the Dal Cais tribe including his mother brutally murdered by a Norse raid when he was only a child, refused to be any part of such a truce. He deserted Mahon with a group of soldiers. They lived in the hills of Munster attacking Norse settlements and disappearing in to the hills. His fame spread throughout the province and infuriated Ivar. Although having only a handful of men, Brian’s skill as a tactician led him to defeat vastly superior numerical forces and led to rumours of a mighty Dalcassian army.

After a number of petty battles, Brian had trained an excellent Dalcassian army to face the Norsemen. The stories of his triumphs had led to vast numbers of young men volunteering to join his side. The feud between himself and Mahon ended. Mahon renounced his truce with the Norsemen and the two brothers rejoined forces. The two men triumphed so far that Mahon took the throne of Cashel in 963 and in 968 at Sulchoid in Tipperary, the two brothers completely overtook Ivar’s forces and marched on Limerick while Ivar fled back to the Norse lands. The Norse tyranny in Munster thus collapsed and Mahon ruled peacefully for eight years. However, Ivar returned to Ireland and plotted the murder of Mahon. After Mahon’s death, Brian not wanting a bloodbath between his forces and Ivar’s, honourably challenged Ivar to open combat, which he won killing Ivar. Brian succeeded his brother as head of the Dal Cais and immediately took the field against his brothers enemies. In 978, he defeated the King of Cashel in battle. Step by step he established himself in the Kingship of Munster and fortified the province. In 983 and 988, his fleets ravaged Connaught and plundered Meath.

Meanwhile, another great leader had arisen in the North, Malachy the second, the Ui Neill King of Tara. Malachy was born in 948, became King of Meath and in 980, High King. This he achieved at the battle of Tara in 980 where he overthrew a Norse Army and took Dublin. A clash between the two men was inevitable. At last, in 998, they met and divided Ireland between the two of them, Brian becoming the King of the South and Malachy of the North.

By 1002, the joint sway of Malachy and Brian could not last. Malachy, being unable to gather enough support to take on the mighty forces of Brian, allowed Brian peacefully to take over his lands. This was the greatest moment in the history of native Ireland. Brian, by his title, “Ard Ri”, was claiming the monarchy of the whole Gaelic race. Before Brian, and Malachy, Ireland was divided in to a number of petty kingdoms, sometimes at peace, sometimes at war with one another. The Vikings themselves joined in the struggles between the Irish kingdoms and also fought bitterly among themselves. There was no one king up to this who was responsible for the defence of Ireland against the Vikings and had control over the entire island.

Brian had much to do as High King to lift Ireland out of the ruins of the Norse Age. He rebuilt ruined churches, built others, he sent overseas to replace lost books and artefacts and all that he possibly could to heal the wounds of the past two centuries of Norse pillage.

In 1013, the Leinstermen and the Dublin Vikings revolted against Brian. Mael Morda, King of Leinster, allied himself with the Dublin Vikings and went to war with Brian. The Dublin Vikings sought allies overseas. The great sigurd, Earl of Orkney, came with a large contingent. While other Viking contingents came from as far afield as Iceland and Normandy. Brian gave them Battle at Clontarf on Good Friday, 1014 and defeated them. However, as the Vikings were retreating, one of their leaders, Bothair, murdered Brian.

After this, Malachy resumed his position as High King and the Dal Cais strength remained only in Munster. The Viking presence in Ireland continued after Brian’s death but their military power was crushed. They remained in the country as traders and intermarried amongst the native Irish. Ireland was never again to have a King to control the entire of the island and the cost to Ireland and to Brian of crushing the Viking power in this country was a great one, for Ireland was never again to have a true “ARD RI”.

Bloody Acre, where Brian Boru was killed in 1014. South of the Tokla River in northwest corner of what is today Glasnevin Cemetery, two miles north of the Dublin city center. Source: Ordnance Survey Ireland.

Table of Contents     

31 Generations: Brian Boru to Conor O'Brien 29355

Conor Myles John O'Brien, who was born in 1943 and lives in Thomond House near Dromoland Castle. He traces his ancestry back to Brian Boru, who is No. 105 in the pedigree shown below. He has had his DNA tested at Family Tree DNA and is O'Brien 29355, with the SNP FGC13418. See the Results pages of: L226 DNA Project and O'Brien DNA Project. He shares the SNP FGC5659 with over 50 other O'Briens, all of whom are likely to be descendants of Brian Boru. See Irish Type III DNA.

The pedigree back to Generation 91, Cas, is from two sources.

• John O'Hart's 1892 Irish Pedigrees
  • Generations 91 (Cas) to 104: "O'Brien (No. 1) King of Thomond," pages 154-162
  • Generations 105 (Brian Boru) to 120: "O'Brien (No. 1) King of Thomond," pages 154-162
  • Generation 121: "O'Brien (No. 2) Marquises of Thomond," page 163
  • Generations 122 to 131: "O'Brien (No. 5) Barons and Earls of Inchiquin," pages 169-170
• Burke's Peerage
  • Generation 132: Edward Donough O'Brien, 14th Baron of Inchiquin (M, #17941)
  • Generation 133: Lucius William O'Brien, 15th Baron of Inchiquin (M, #28636)
  • Generation 134: Hon. Fionn Myles Maryons O'Brien (M, #484007)
  • Generation 135: Conor Myles John O'Brien, 18th Baron of Inchiquin (M, #484010)

Google Books has made the 1892 edition available online: Volume I and Volume II. The University of Pittsburgh Library System has made the 1892 edition available online as a PDF file or Ebook: Volume I and Volume II. Library Ireland has made a transcript of Volume I available online.

O'Hart's 1892 Irish Pedigrees includes 12 ancient names with pedigrees related with Brian Boru. Modern-day people with these same names have been found to have the same DNA--what we call L226 and Brian Boru DNA. Many of these names appear on pages 154-162 of Vol. I, O'Hart, which give the Brian Boru pedigree back to Cas, from whom comes the name "Dalcassians."

Burke's Peerage refers to Peerage, Baronetage & Knightage, Charles Mosley, editor, 2003. Darryl Lundy, from Ngaio, Wellington, New Zealand, has put Burke's Peerage online at The Peerage. Link's to Burke's Peerage here are to Lundy's The Peerage.

Generations 120 to 131 are available from Burke's Peerage (The Peerage) as well as O'Hart's 1892 Irish Pedigrees.

Generations 91 to 120: O'Hart's 1892 Irish Pedigrees, "O'Brien (No. 1) King of Thomond," pages 154-162

Generation 121: O'Hart's 1892 Irish Pedigrees, "O'Brien (No. 2) Marquises of Thomond," page 163

Generations 122 to 131: O'Hart's 1892 Irish Pedigrees, "O'Brien (No. 5) Barons and Earls of Inchiquin," pages 169-170

Generations 132 to 135: Burke's Peerage

Table of Contents     

Brian Boru Timeline

Below is a timeline for L226 and Brian Boru DNA and ancient pedigrees.

Table of Contents     

L226 and O'Brien Testing Projects

If you are a male with the name associated with Brian Boru, you may benefit from participating in the L226 DNA Project at Family Tree DNA. You should also participate in the surname project. There are two O'Brien projects: O'Brien DNA Project and Bryan DNA Project. But beware of the fact that practically all Irish surnames have multiple origins.

The L226 DNA Project was started by Dennis Wright in December 2009. The project is designed to encourage men with likely L226 DNA to test for the L226 SNP (single nucleotide polymorphism). It is limited to those who have tested positive for the L226 SNP or have ordered the test. You are likely to test positive for the L226 SNP if you are in the R1b1a2 haplogroup and have values of 8-9 for marker 459. These are the 14th and 15th markers. Having an historical surname does not guarantee that you will have L226 and Brian Boru DNA because most surnames have multiple origins.

You can participate in the L226 project as well as a project specifically set up for your surname. There is no additional cost for being part of two projects.

By testing the Y-chromosome DNA, males can determine the origin of their paternal line. Note that the Y-chromosome DNA strictly checks the paternal line, with no influence of any females along that line. Females do not receive the Y-chromosome, and therefore females cannot be tested for the paternal line. If you are a female and would like to know about your paternal line, you would have to find a brother or a male relative from that line willing to be tested.

The two swabs and scraper tubes in the FTDNA Kit. For more on how it's done, see "DNA Collection Method" by Dave Dorsey.

Y-chromosome DNA goes back male to male like traditional surnames.

You sign up online for FTDNA and they deduct the cost from your credit card. They send you in the mail a kit containing two scrapers that you use to swab the inside of your cheeks in four-hour intervals. You return the scrapers in receptacles and mailer provided in the kit. You get final results on line two months later.

If you decide to have your DNA tested, you should consider the ultimate test, which is Big Y-700. There are intermediate tests, but they will not tell you whether you have BriaBrian Boru DNA.

Most names have multiple origins. For this reason, your results may show that your DNA does not match the Brian Boru DNA, which will lead you in a different ancestry direction.

Table of Contents     

Brian Boru Big Y SNP Tree

The Big Y test was introduced by FTDNA. As of February 2021, over 50 O'Briens had done Big Y and were found to have Brian Boru DNA, including one with a pedigree back to Brian Boru, O'Brien 29355.

Big Y results can be seen on FTDNA's L226 DNA project, as well as Alex Williamson's FGC5659 Big Tree.

The following pointers will help to navigate the Brian Boru Big Y SNP Tree shown in the window below.

1. SNPs. SNPs (e.g., FGC5659) are single nucleotide polymorphisms, or mutations, found on the Y chromosome of male BIG Y testers. SNPs that are inherited by two or more testers allow the creation of tree branches with named SNPs.
2. Testers. After each SNP are the names of Big Y testers whose DNA named the SNP.
3. Unique STRs. Shown after some SNPs are STRs (short tandem repeats) that are unique for that SNP.

Dennis Wright, in his L226 Big Y SNP Testing, says that the FGC5659 SNP seems to have originated in Brian Boru or his father. Dennis is responsible for many of the SNPs descovered for L226 and Brian Boru, particularly the ones starting with DC. The letters DC at the head of SNPs stand for Dál Cais. (See: ISOGG Y-DNA Tree.)

Brian Boru Big Y SNP Tree

(See also Abridged Tree.)

Table of Contents