My ancestors - Blennerhassett - Contents

Theory of O'Connell descent

In 2025, I formed a possible extraordinary theory that my ancestor George Cashel (born 1807) may descend somehow from the family of Daniel O'Connell, "The Liberator" and his wife and cousin Mary O'Connell.

Pursuing this, it is beginning to look likely that our descent is from the family of Mary O'Connell's mother Ellen Tuohy. If so, this is a theory of Tuohy descent, not O'Connell descent. This theory is not proved. But there is an increasing amount of evidence. We may be on the end game of this long hunt.

Background: George Cashel descends from Blennerhassett

The background is that my ancestor George Cashel emerged in some irregular way from the landed gentry Blennerhassett family of Co.Kerry. Something like an affair or a runaway marriage in about 1806. This was already known by my family, but it took decades to prove that he is in fact closely related to the Blennerhassett Baronets family. See the proof of connection to the Blennerhassett Baronets family. I believe I have proved from documents and DNA that George Cashel must descend somehow from Robert Blennerhassett (died 1765), father of Sir Rowland Blennerhassett, 1st Baronet.

The most likely theory is that George Cashel is the natural son of one of six Blennerhassett men, namely the five sons of the 1st Baronet, and their 1st cousin. That is, six grandsons of Robert Blennerhassett. In 1806, four of the six men were married some years. One was recently married in 1805. Another married in 1808.

Something irregular happened. One imagines it would be the old story: A wealthy Blennerhassett man, perhaps married, has a brief affair with a lower class woman, and then leaves her with the baby.

However, this page suggests something much more exotic may have happened: A wealthy Blennerhassett man, definitely married, has an affair with a woman of his own class, and ruins her. Let us lay out the evidence so far.

Unexplained DNA matches

The theory begins with Sheila O'Connell, who has strong, unexplained DNA matches with multiple parts of the family below George Cashel.

• Sheila O'Connell is a DNA match (through unknown line) of (Blennerhassett Cashel, 1st marriage):
  • Desmond Conacher. DNA match is size 26 centimorgans (cM).
  • Madeline Conacher. 25 cM.
  • Rosaleen Riordan. 24 cM.
  and of (Blennerhassett Cashel, 2nd marriage):
  • Derval McGrath. 28 cM.
  • Frank McGrath. 26 cM.
  • Helen McGrath. 25 cM.
  and of (Cashel of Alaska line):
  • Jean Fleek.

• These DNA matches are pretty big. They indicate a common ancestor around 1800.
• The DNA matches do need explaining. But this by itself is not unusual. Lots of DNA matches need explaining, and often are never explained.
• Normally I would not start with DNA matches and search for an explanation, because you never find one. I go the other way. Construct a theory and then see if DNA matches support it.
• However, this one is different. Systematically going through all shared matches groups of all my people on Ancestry suggests Sheila O'Connell as the strongest unexplained group of matches in all my George Cashel descendant accounts. So it is worth a closer look.

• How could we be related to Sheila? We look first at the Cashel family. The DNA matches are spread across different sons of George Cashel (and two different wives of one of the sons), so therefore the common ancestor must be through either George Cashel (Co.Kerry) or his wife (Co.Tipperary).
• Then looking at Sheila O'Connell's ancestors, it seems the match must be through either the O'Connell or Leyne lines, both in Co.Kerry.

The likely lines (O'Connell and Leyne) are linked to Blennerhassett

• The next step is that we see that Sheila's ancestors through O'Connell and Leyne are deeply connected with Blennerhassett both socially and by blood. This is now starting to look interesting.
• First, by blood. She actually descends in two different lines from early, 17th century Blennerhassetts. But that is too far back to explain the strong modern DNA matches. The common ancestor must be more recent.
• She does not apparently descend from the Blennerhassett Baronets branch in any way. So that is not the answer to the DNA matches.

• This raises the extraordinary possibility that this is George Cashel's parent who is not the Blennerhassett Baronets line.
• Have we found the line of George Cashel's mother? That is, his mother is not a lower class woman. Instead she is an upper class or upper middle class woman from this branch, which we know is socially connected with the Blennerhassetts. She has an affair with a Blennerhassett man from the Baronets branch, and they are George Cashel's parents.

O'Connell fits better than Leyne

• Looking at the Leyne line, it is hard to see how a mother for George Cashel could fit in. Maurice Leyne, MD, marries in 1786, which is a bit late for him to have a daughter who is George Cashel's mother. Maybe Maurice has a niece that would fit. We will keep looking.
• Over in the O'Connell line, we are looking at the family of Thomas O'Connell, MD. The dates and general layout fit much better to have a daughter who is George Cashel's mother.
• There is some uncertainty about the number and names of the daughters of Thomas O'Connell, MD, including an unnamed daughter who married Patrick O'Mara.
• Could George's mother be an O'Connell, a sister of Mary? Could Daniel O'Connell be our ancestral uncle? What a discovery that would be.

O'Connell is linked to the Blennerhassett Baronets

The evidence then got more exciting:

• We discovered that Ellen Tuohy, widow of Thomas O'Connell, MD, married in 1803 to Henry Blennerhassett, 1st cousin of Sir Rowland Blennerhassett, 1st Baronet.
• In fact, her 1st husband Thomas O'Connell, MD (who died in 1785) was himself 2nd cousin of the 1st Baronet. Her children were 3rd cousins of the 1st Baronet's sons.
• But her 2nd marriage in 1803 is striking. That means that after 1803, Ellen's unmarried daughters and other close relations are a lot more likely to be socialising with the 1st Baronet's sons. And hence an affair could happen around 1806.
• Quite a discovery. This is beginning to look beyond coincidence.

Miss Tuohy

We then discovered a tragic 1806 story about a Miss Tuohy, written in a document by the daughter of Mary and Daniel O'Connell, Ellen Fitzsimon. Her account of the story is that:

• Miss Tuohy (no first name) is 1st cousin of Mary O'Connell, through her mother Ellen Tuohy.
• Miss Tuohy accepted the hand of an unnamed young barrister, a friend of Daniel O'Connell. But he was persuaded to call it off, causing her great distress.
• Mary and Daniel O'Connell took care of her, but she died on their journey from Kerry to Dublin in late 1806. It seems she may have killed herself.
• The barrister never got over it and never married and died young.

So could this be a Blennerhassett man and a Tuohy girl, and them be the parents of George Cashel? And the mother killed herself after giving birth? And the baby was adopted and got a new name? It is incredible that there is such a dramatic, and apparently unpublished, story in Daniel O'Connell's life. And in the exact year, 1806, that we are looking for such drama to explain George Cashel.

The cousin seems to be Kitty Tuohy, who is mentioned in a letter of Apr 1806 as unmarried, and being teased about romantic possibilities.

However there are some issues with the story. The story does not mention a pregnancy. (But that could be covered up.) Also, none of our six Blennerhassett men died unmarried.

The Miss Tuohy story may be the breakthrough

If the Miss Tuohy story is changed slightly, this may be the breakthrough:

• First, Ellen Fitzsimon did not witness these events. She was only a baby at the time. She was told this story later by her parents. And maybe they sanitised and romanticised the story a bit.
• In particular, maybe the man was married, and that is why it led to inevitable tragedy.

• But there is enough in her story to get excited about because in fact there is a young lawyer among the six Blennerhassett men, and he is connected to Daniel O'Connell. He is "Black Arthur" Blennerhassett, of Blennerville. He was born in 1776, and entered King's Inns in 1794. Daniel O'Connell was born in 1775, and entered King's Inns in 1795. As two Kerry men studying law in Dublin, of course they knew each other from then.
• Arthur must be the "Arthur Hassett" who is mentioned in a letter as dining with the O'Connell family in August 1805. Clear evidence of one of our six Blennerhassett men socialising with the O'Connells just before the time an affair could have happened.
• He is a young lawyer, and a friend of Daniel O'Connell, and the problem is he is married.

Theory: George Cashel is the son of "Black Arthur" Blennerhassett and Kitty Tuohy

Here is a guess at what we think maybe happened.

Background:

• Daniel O'Connell is friends with "Black Arthur" Blennerhassett since his student days at King's Inns.
• Arthur marries in 1799 to Helena Jane Mullins.
• Daniel marries in 1802 to Mary O'Connell, Arthur's 3rd cousin
• Mary's mother Ellen Tuohy marries in 1803 to the 1st cousin of Arthur's father.
• Arthur is a married man, friends with the O'Connell family, dining with them in Aug 1805.
• Mary O'Connell is close friends with her young cousin Kitty Tuohy, who is mentioned in a letter of Apr 1806 as unmarried and being teased about romantic interests.

The affair:

• "Black Arthur" Blennerhassett and Kitty Tuohy have an affair.
• Kitty gets pregnant and gives birth to a baby, probably in 1807.
• Kitty, in great distress, dies (maybe kills herself), probably in 1807.
• The baby is given up for adoption, probably by a family called Cashel. The baby is not called either Blennerhassett or Tuohy.
• The suspect for the family that raised the baby would be the Stephen Cashel family of Tralee. This would explain George's middle initial "S." It would also explain his attachment to the name "Agnes" for his daughters. Agnes Noonan would be his adopted mother. It would mean George was baptised Catholic in 1808.
• An adopted family would also explain why George Cashel's descendants do not DNA match any Cashel in the world - which otherwise is hard to explain. George Cashel is in fact a Blennerhassett.
• George Cashel's great-grandmother Elizabeth Fitzmaurice [born 1725] was alive when he was born.

Aftermath and discussion:

• It is strange that no one from the adoptive family ever turns up later in his life. But he did move far away.
• It is interesting that my family remembered Blennerhassett, but not the much more famous Daniel O'Connell. But this could be explained if Daniel O'Connell is not actually a relation, and our descent is from Blennerhassett and Tuohy.
• "Black Arthur" may be a name that Daniel O'Connell gave to Arthur after these events.

• It looks increasingly likely that the Arthur Blennerhassett, JP, recommending George Cashel for the police in 1828 is his own father.
• However, on a darker note, Arthur's will in 1838 is unusual because it lists a large number of family members in line of succession to his property if lines ahead of them fail. Was this done to make sure George Cashel would not inherit?
• George Cashel was Arthur's only surviving son. Arthur only had one son, Rowland, and it seems he died early. He is not mentioned in Arthur's will. George was the only living son, and Arthur would know that. George might have inherited Blennerville!

Issues and further proof needed

This theory explains everything. But we are missing the last pieces of paper evidence:

• We have not proof that the man in the 1806 story was a Mr. Blennerhassett or "Black Arthur".
• We have not proof there was a baby or that it was adopted by Cashel.
• The DNA is a bit of a worry. The DNA matches with Sheila O'Connell seem a bit too strong if the common ancestor is in the Tuohy line. It is one generation further back than we expect. But maybe it is possible.
• But what are the odds that DNA led us into a certain family, and then we found a tragic story of 1806 in that family?

More work to be done. But we may be near the end of the hunt.

This problem was almost impossible to solve

This problem was almost impossible to solve:

• A family story of Letitia Blennerhassett, but there was no Letitia Blennerhassett.
• A family story of a runaway marriage, but there was no runaway marriage.
• There was not even a Miss Blennerhassett.
• There was not even a Mr. Cashel.
• There was not even a Miss Cashel.
• Neither parent of George Cashel was called Cashel.
• George Cashel is adopted and is not related to any other Cashel.
• I should have been searching for Blennerhassett with Tuohy. But how on earth would I know that?

No wonder all my searches led nowhere! The facts were at odds with all the terms I was searching for.

• Even when I found George Cashel's baptism of 1808, I did not recognise it. It made no sense.
• Even when I found the 1806 story on microfilm in the NLI, I did not immediately recognise it. I had to re-calibrate all my thinking to realise this could be our story. It took a few days to see that I had really found the story.

I think this problem could never have been solved before DNA. Without DNA, I would never have looked at so many O'Connell papers. I would probably never have found the 1806 story. Even if somehow I found the story of "Miss Tuohy" in 1806, I would never think it was us, and I would just pass on. I think this problem could never have been solved before DNA, before 2010.

I had already discovered George Cashel's baptism by Jan 2004 (when my father was alive), but I could not see it. It did not make sense.
Note I had not yet discovered it in Aug 2003.

Mary O'Connell, who married Daniel O'Connell.
Is her 1st cousin Kitty Tuohy my ancestor?

"Arthur Hassett" dining with Daniel O'Connell's father and Mary O'Connell in letter of Aug 1805.
Did Arthur soon after have an affair with Mary's cousin Kitty Tuohy, and are they my ancestors?

"Black Arthur" Blennerhassett mentioned in letter of Jan 1823 from Daniel O'Connell to his wife.
Is Black Arthur my ancestor?

The tomb of Arthur Blennerhassett.
Is he my ancestor?