Late Medieval Branches of the Farrells of Annaly - introduction

Irish medieval genealogies are the oldest in Europe. They were compiled by monks and scribes from the 7th century onwards and comprehensive compilations were created in the 1600s. These genealogies stretch from the pre-Christian era, up to the arrival and adoption of literacy in Ireland (about 500 AD), then to the formation of surnames in Ireland (roughly 950-1250 AD), and occasionally up to the demise of the Gaelic clan system in the 1600s. You can read a brief account of the history of these genealogies here.

In my presentation at the recent Clan Gathering (see previous post), I discussed the medieval genealogies of the Farrells of Annaly (Longford). The Farrell name arose from Feargal, born about 980 AD. The genealogies then follow the direct-male-line of the Farrell chieftains for several centuries and several branches are recorded up to the 1600s (see the relevant chapter of my YouTube presentation here). 

In addition, I discussed how ongoing research has established (with 80-90% confidence) that the section of the Farrell medieval genealogies from about 800-1050 AD is broadly correct and there is no indication that they have been manipulated for socio-political reasons (see here). The evidence for this is based on a comparison of two types of "family tree" - one genealogical, the other genetic. 

The genealogical family tree is based on the medieval genealogies which describe how the surnames Farrell, Reynolds, Shanley, and Mulvey stem from a common ancestor (Cromán) born about 800 AD. These surnames branch off from each other at different points in the tree, thus creating a particular branching structure. This tree is known as the CAST (Clan-Associated Surnames Tree) and is based solely on the documentary evidence. 

On the other hand, the genetic family tree is based on the branching structure created by various DNA markers detected by the Big Y test. In addition, clusters of people with the same surname sit on particular branches of this tree, which is known as the DAST (DNA-Associated Surnames Tree).

When we compare the two types of tree (CAST vs DAST), we find that 1) the branching structure is the same in both trees; 2) the age of the branching points in the genetic tree is consistent with those estimated for the genealogical tree; and 3) the surnames on the genetic tree sit exactly where we would expect them to based on the genealogical tree. This provides strong supportive evidence that these medieval genealogies are broadly accurate.

Furthermore, this means that anyone who is in Group 2 of the DNA Project can now claim Feargal as their direct ancestor, but can also (with 80-90% confidence) claim his ancestors back to about 500 AD when the written word began to be used in Ireland. This adds an extra 17 generations to your family tree, stretching from 1000 AD back to 500 AD. 

Prior to 500 AD, the genealogies record additional ancestors, but this earlier portion of the genealogies is less reliable because the names were passed on via oral tradition (and therefore there is a higher chance of mistakes being made).

The section of the Farrell medieval genealogies after 1050 AD includes at least 10 descendant lines, some of which extend to 1600 AD. That just leaves a 200 year gap between 1600 and 1800 (where many Irish family trees hit a Brick Wall due to the paucity of records). However, it may be possible bridge this 200-year gap by using DNA (specifically the Big Y test) to link specific people to specific genetic branches associated with the Farrells of Group 2. 

In so doing, we jump across the divide of absent documentation and reconnect with some of the late medieval branches described in the medieval genealogies. And if we can do this, it means that for some people in the project, they (and everyone in their families) will be able to extend their Farrell line from 1800, back to 1600, and back to 1000 AD (to Feargal) and back to 500 AD (to Earcol). That is a jump from 5 generations to 49 generations of named Farrell ancestors, with a gap of about 3-6 generations where named ancestors are replaced with DNA markers.

And that's a wow!

In the next article, I'll be taking a deeper dive into the Late Medieval Branches of the Farrells of Annaly.

And one of those branches could be yours ...

Maurice Gleeson

Aug 2026

Farrell DNA Project update 2026 - can Big Y take us back via 49 generations of named ancestors to 500 AD?

The Farrell Clan Gathering 2026 was recently held in Longford and I have to congratulate the organising committee for such a well-organised series of events. It was wonderful to meet old friends and make new ones. And it was truly an international event with local Farrells joined by people from the UK, the US, Canada, Australia, New Zealand, Spain and Argentina. I was even able to practice my Spanish! 

The parade of country flags through the streets of Longford stopped the traffic and drew a huge amount of interest from local people - everyone had their iPhone raised taking videos. And, to the delight of the local children, the Brooklyn crew handed out free beaded necklaces to everyone along the way! It was great to be part of such an open declaration of cultural pride.

Another high point for me was the inauguration of our new chieftain, Charlotte Farrell. We all watched on the huge video screen as Charlotte and a group of celebrants climbed up to the top of the Granard motte (The Hill of the Sun). Modern archaeological scholarship considers Granard the most likely inauguration site of the Ó Fearghail Bán, the northern branch of the O'Farrell dynasty that ruled Annaly. The inaugaration took place in the shadow of the statue of St Patrick, thus bringing our rich Celtic and Christian heritage together.

Several of the events during the week gave us a rich insight into the past. The visits to Castlecor House and Strokestown Park House allowed us a hands on experience of life in Longford in the 1800s and in particular during the years of the Great Famine (1845-1848). The visit to  Corlea Trackway took us back over 2000 years to a time when our ancestors were building roads with wood. The trackway (in Irish, togher) is the largest of its kind to have been uncovered in Europe.

To see all the Farrell pedigrees on the wall for the genealogy evening on Wednesday was particularly gratifying. My thanks to Susan Farrall who did a fantastic job coordinating this. Several people made possible connections on reviewing these pedigrees and conversations stretched well past everyone's bedtime.

The Ambassadors Reception on the last day was hugely motivating. It was great to hear what the various ambassadors (there are 15 of them) are doing in their respective countries and all the positive feedback that was directed toward them and the organising committee in Longford was especially inspiring. As the Gathering is only held in Longford every 4 years, I suggested that the ambassadors could consider hosting a similar Gathering in their own countries during the 4 year interval between Gatherings in Ireland. I for one would love to travel to every country that was represented at the Gathering.

On the Wednesday evening (July 22nd) I gave a presentation on genealogy, including an update on the Farrell DNA Project, focussing on Group 2. You can see it here or by clicking on the image below. 

The key question addressed by the presentation is: can DNA take your Farrell ancestry back 1,500 years? This presentation explores how to get started with your Farrell family tree, make the best use of historical records, and combine them with DNA evidence to overcome even the toughest genealogical brick walls. I describe how the Farrell DNA Project has uncovered the Y-DNA signature of the Farrells of Annaly (County Longford) and how, as the project expands, it may enable participants to connect with documented medieval pedigrees. The final portion of the presentation showed how it was possible for a select number of people in the DNA project to potentially extend their Farrell pedigree from 5 generations (i.e. stuck at 1800) to 49 generations (c.500 AD) with a gap between 1800 and 1600 bridged by the Big Y test. There were audible gasps from the audience and a couple of "wows". 

I had negotiated special discounts on DNA tests for the Farrell Clan Gathering and altogether 11 people bought DNA tests at the discounted prices. Several others were interested in getting cousins tested or upgrading their results to the Big Y test.

The good news is that the FTDNA Summer sale has just started (31st July) and the same discounts that we had at the Gathering are now available for everyone. So now is a perfect time to take advantage of the discount on the Big Y upgrade (which would save you up to US$70). Here are the key discounts available but you can find out more on the FTDNA website.

There are several people who should consider upgrading to the BigY test:

1. anyone in Group 2 (The Farrells of Annaly)
2. anyone with an extensive pedigree that stretches into the 1700s or beyond
3. anyone with a known or suspected connection to the O'Farrell Bawn or the O'Farrell Bwee
4. anyone with a known or suspected connection to some of the late medieval genealogies, which include the following:
• the O'Farrell Bawn or the O'Farrell Bwee as mentioned above
• the O'Farrell families of Rathline, Ballinalee, Edgeworthstown, Longford town, Granard, Magh Treagha, Caltragh & Corlea, and Clanhugh

I will post these late medieval genealogies on this blog in subsequent articles.

I have also divided the video of my presentation into chapters and you can go straight to any particular chapter by clicking the relevant link (on the timestamps below). YouTube Chapters (click any timestamp below to go to that specific chapter)

00:00 – Introduction & Welcome

An introduction to the Farrell Clan Gathering, the aims of the presentation, and how DNA is transforming Irish family history research.

02:40 – Building Your Farrell Family Tree

Learn how to get started with your family tree using Ancestry, WikiTree and free Irish genealogy resources, with practical tips on subscriptions, AI tools, and overcoming common research challenges.

14:55 – DNA Testing Explained: Y-DNA, mtDNA & Autosomal DNA

An easy-to-understand overview of the three main types of DNA tests, what each one can tell you, and which tests are most useful for Irish genealogy.

17:55 – Case Study: Breaking thru a Brick Wall with Autosomal DNA

A real-life example showing how shared DNA matches, family trees and collaborative research uncovered seven previously unknown generations of ancestors, adding a total of 23 additional ancestors beyond the Brick Wall.

25:44 – Using Autosomal DNA Clusters to Break Thru Your Farrell Brick Wall

Discover how clustering shared DNA matches can identify unknown common ancestors, organise distant cousin matches, and provide new clues when documentary records have run out.

34:30 – Using Y-DNA37 to Find Your Farrell Genetic Group

An introduction to the Farrell DNA Project, how Y-DNA follows the direct paternal line, and how it can determine which of the major Farrell genetic groups your family belongs to.

38:45 – Big Y Testing and the Farrells of Annaly (Group 2)

See how Big Y testing is reconstructing the genetic family tree of the medieval O'Farrell dynasty, identifying branches of the Farrells of Annaly and linking modern families to their historic origins.

58:10 – CAST vs DAST: the Big Y helps validate the Medieval Genealogies

Discover how comparisons between Clan Associated Surname Trees (CAST) and DNA Associated Surname Trees (DAST) provide strong evidence supporting the accuracy of the medieval O'Farrell genealogies and their related clans.

1:01:10 – Future Directions: Connecting Your Farrell Line to 500 AD

Explore how combining documentary genealogy, autosomal DNA, Y-DNA and Big Y testing could eventually bridge the gap between your family tree and the medieval O'Farrell pedigrees - potentially tracing your paternal ancestry back to the arrival of literacy in Ireland around 500 AD. That would give you 49 generations of Farrell ancestors, with a gap of some 3-6 generations where DNA markers substitute for named ancestors.

Maurice Gleeson
July 2026