When people descend from a common ancestor and share identical segments of DNA (presumably inherited from that common ancestor), it’s known as a triangulation group.
That’s what we’re looking for in this phase of our genetic genealogy project – so we can determine where our earliest known Somerset Sainsbury ancestor came from.
What is a triangulation group?
So in this phase of the project we’re looking for (a) anyone who shares an identical segment of DNA with (b) any documented descendants of Richard Sainsbury of north Somerset.
But to establish a triangulation group to support this project’s leading theory (i.e., that the Richard Sainsbury of north Somerset in the late 1700s was the Richard Sainsbury born in Urchfont in 1708) that person also needs a well-documented family tree going back to any ancestor of Richard Sainsbury of Urchfont (1708-?):
Why are we looking for DNA matches related to any ancestor of Richard Sainsbury of Urchfont?
Because after more than a year of searching family trees, uncovering genealogical documents, and identifying DNA matches to about 100 known Somerset Sainsbury cousins with DNA tests, Richard Sainsbury of Urchfont became the leading candidate in our quest to solve The Mystery of Richard Sainsbury.
If, if, then . . .
If a documented descendant of any ancestor of Richard Sainsbury of Urchfont shares DNA with any descendant of Richard Sainsbury of north Somerset (d. 1785) – and if no other genealogical explanation can be found – then we can assume we’ve found a triangulation group that more-or-less proves that the Sainsbury family of north Somerset is a branch of the Sainsbury family Urchfont, Wiltshire.
Until now, however, we lacked a triangulation group in which one or more descendants of Richard Sainsbury of north Somerset could be shown to share identical segments of DNA with one or more descendants of the “other” Richard Sainsbury’s Urchfont-area ancestors.
Of course, that could be because Richard Sainsbury of Urchfont is not our ancestor, and we’re therefore barking up the wrong family tree.
On the other hand, we’ve established a body of evidence (and a large set of non-triangulated genetic matches) that strongly indicates Urchfont as our Sainsbury place of origin.
So the lack of triangulated matches to date could also be because the probability that two cousins at this genetic distance will share enough DNA for the relationship to be detected is probably less than 0.002%. (Source: https://isogg.org/wiki/Cousin_statistics).
Which brings us to . . .
The will of Elizabeth Jarvis (d. 1602)
One hundred and fifty years before Richard Sainsbury appeared in the Bristol area of Somerset, Elizabeth Jarvis of Upavon, Wiltshire, wrote her last will and testament.
Elizabeth had been a widow for 17 years – ever since the 1585 death of her husband, John Jarvis, haberdasher of Upavon.
As an Elizabethan haberdasher, John would have sold an assortment of small goods:
buttons, pins and fastening hooks, thimbles, silk threads and trimmings and laces of all kinds as well as felt hats and caps, gloves of all sorts, hosiery, purses of taffeta and leather and red satin pin cushions . . . playing cards, spectacles, combs, crystal glasses, ordinary drinking glasses, wooden plates, knives and even pictures.Source: T. Cooper. (2003). What was it like to go shopping in Elizabethan London? https://www.npg.org.uk/blog/elizabeth-i-installation
In effect, John Jarvis ran the Elizabethan equivalent of a Dollarama or Poundland.
In her will, written 17 years after he husband’s death, Elizabeth Jarvis bequeathed the residue of her estate to three of her children: John, Mary, and Dorothy. She also named her son-in-law (and Dorothy’s husband) John Sainsbury of Urchfont:
John Sainsbury and Dorothy Jarvis, who married in Urchfont in 1587, were the great-great grandparents of Richard Sainsbury of Urchfont.
Any DNA shared by descendants of Dorothy’s parents, John and Elizabeth Jarvis, if also shared by one or more Somerset Sainsbury descendants would form a triangulation group of enormous significance for this project’s main goal: to solve The Mystery of Richard Sainsbury of north Somerset.
Absent any other genealogical or genetic explanation, a triangulation group made up of descendants of John and Elizabeth Jarvis of 16th-century Upavon, Wiltshire and any descendants of Richard Sainsbury of 18th-century Somerset would pretty much prove that our Somerset ancestor, Richard Sainsbury, was the same Richard Sainsbury who was born in Urchfont in 1708.
And, in fact, that’s exactly what we’ve found.
Triangulation Group #1
Using GEDmatch and MyHeritage, we identified two Somerset Sainsbury cousins in Canada who share an identical segment of DNA with two documented descendants of John and Elizabeth Jarvis of Upavon.
One member of this group lives in New Zealand (Kia Ora, NR, for your help with this research!) the other lives in the United States.
Both have well-documented family trees going back to John and Elizabeth Jarvis of Upavon. No other family lines appeared to explain their genetic and genealogical relationship, which is indicated in this downloadable family tree:
Four other were identified who share the same segment of DNA but their family trees could not be traced back to a common ancestor. (One ended in colonial America, three ended in Warwickshire and/or Staffordshire.)
Our first good evidence
It’s clear from their family trees that NR and DS very likely (in fact, almost certainly) inherited this segment of DNA from their most recent common ancestors, John and Elizabeth Jarvis of Upavon.
And the only reasonable way to explain the presence of the same segment of DNA in two Somerset Sainsbury descendants is that their documented ancestor, Richard Sainsbury of north Somerset, must have been Richard Sainsbury of Urchfont – the great-great grandson of John and Elizabeth Jarvis of Upavon.
This DNA match is a significant indication that Richard Sainsbury of Urchfont – the youngest son in once-prosperous family that had fallen on some degree of economic hardship – migrated to north Somerset, married there in 1745, and became the head of a large family that now spans the globe.
The first of many?
Over the course of this project we’ve identified almost 100 genetic matches among Somerset Sainsbury descendants to descendants of Richard Sainsbury’s Urchfont-area ancestors.
This is the first triangulation group (with identical DNA and well-documented trees) to support our leading theory, but if it’s valid, there should be a few others waiting to be discovered.
Any of the “non-triangulated” matches identified in this project could become triangulation groups if those involved are willing to upload their Ancestry DNA tests to GEDmatch and MyHeritage.
That’s what this phase of the project is all about. Finding triangulated matches to solve The Mystery of Richard Sainsbury of north Somerset. And for that . . .
We need your help
Are you a Somerset Sainsbury cousin or a Sainsbury descendant with a match to a Somerset Sainsbury? Please upload your results to GEDmatch and MyHeritage — for free!
The Ireland Davis family blog provides an excellent, easy-to-follow set of instructions on how to download your results from sites like Ancestry and upload them to GEDmatch.
To upload to MyHeritage, you need to download your test from Ancestry:
and then upload it to MyHeritage (for free):
After you create a MyHeritage account, you can change your account settings to decrease or eliminate any emails they will send you.
If you need help with any of the steps, please use the Comments section or the Contact button at the top of this page to get in touch.