How To Discover The Secrets of Your Illegitimate Ancestors

Discovering an illegitimate ancestor in your family tree is exciting. It presents a mystery to be solved. A case to be cracked. What were the circumstances of their birth? Who were their parents? But, these curious ancestors also pose some difficulties. How can we track down unnamed fathers? Will we ever know their secrets?

Discover The Secrets of your illegitimate ancestors

For an example of a real case of an illegitimacy mystery, check out my interview with Nick Barratt. Nick revealed his many attempts to discover the identity of the father of his great-grandmother.

Table of Contents

What is an illegitimate ancestor?

Illegitimate means “not recognised as lawful offspring”, specifically because the child was born to unmarried parents. See Merriam-Webster dictionary

When you see genealogists using the term, please know that they are using it as a legal term and not a judgement. As an unmarried mother of 3, I have 3 little illegitimate blighters nipping at my heels so there is certainly no judgement here!!

The legal nature of the term is important and sadly, it’s still relevant. Children born to married parents had greater inheritance rights than children born outside of wedlock.

Whilst registering the birth of my children, their father and I were advised that should we decide to marry, then we should consider re-registering the birth of our children. Just in case we went on to have another child born within wedlock. If we didn’t re-register, then our imaginary “legitimate” child would have greater inheritance rights then our “illegitimate” children. It turns out, this is incorrect and the law was changed in 1987. That’s right…not 1897….1987! Technically, though you still need to re-register your children and can be fined a whopping £2 (that’s right £2) for failure to do so.

Note that being born illegitimate does not necessarily mean that your ancestor was the offspring of a single mother. Or that your ancestors parents never married.

How do I know if my ancestor was illegitimate?

Sadly, our ancestors were often made to feel ashamed of having children outside of wedlock. Especially in cases where no future marriage was planned. There were serious social-economic consequences to having a child outside of wedlock too. The number of jobs that women could do were far smaller than those available to men. Working women were paid less then their male counterparts too. Add to this the complication of an extra mouth to feed and the need to obtain childcare and it’s no surprise many women ended up at the Workhouse. In a judgemental, patriarchal society, a woman with an illegitimate child may have found that her “cards had been marked” and she was considered undesirable to future potential marital partners. This could prevent her from ever gaining the financial security a husband might bring.

This means that our ancestors may have tried to conceal their illegitimate offspring. It’s therefore worth considering less obvious clues, along with the glaringly obvious (such as an ancestor that has the same surname as their mother, an inability to find a marriage record or / and an infant with no father’s name recorded on their baptism / birth record.

The below clues do not always indicate an illegitimacy but they are potential flags that raise questions:

  • Your ancestor grew up in institutions (like industrial schools, workhouses), you don’t find them living with their parents on the various census records.
  • A long gap between the birth of children.
  • A mother and child on a census live without a husband, perhaps with the mother’s family. Mother’s marital status is given as “married”. Further flags should be raised if this happens on several census OR if you later find mother and child on a census in which she is married, the husband is present but mother and child’s surnames now match the husbands and not that of earlier census.
  • Missing births and baptisms.
  • Some ambiguity in a child’s surname, perhaps a name that changes across documents.
  • A middle name that looks like a surname but doesn’t relate to any of the mother’s family.
  • Finding an ancestor with a child, but being unable to find that child’s birth registration – perhaps the child was actually the child of a sibling
    Bride or Groom’s giving their father’s name as something you either don’t recognise OR that differs to the name given on other documents (including re-marriages). Perhaps they were illegitimate and didn’t know (or were unsure of) their father’s name?
  • Upon your widowed (or unmarried) ancestors’ death, their property went to the Crown OR your ancestor is mentioned in the will of someone else, rather unexpectedly. There are various rules around inheritance and some pay provide clues to your ancestors illegitimacy. There is a great summary at FamilySearch.

How did our ancestors try to hide illegitimacy?

Considering the social stigma it is not surprising that some of our ancestors attempted to conceal the illegitimacy of their children. Here are few examples for you based around different scenarios.

Father of illegitimate ancestor
  • If your ancestor was born very shortly (days, couple of weeks) before their parents married they might have held off registering the birth of their child until after their marriage. Similarly, pre-1837 (before centralised birth registration) they may have delayed a baptism.
  • For birth’s after 1837, it is worth bearing in mind that father’s did not need to agree to be named in order to have their name recorded on the birth certificate. A woman could say that the father was a labourer called William Smith. It’d be hard to prove otherwise, when William Smith could be any number of different people. Although, rules changed in 1875 requiring both mother and father to agree to be named, it doesn’t take much of a stretch in imagination to think of ways around this if someone really wanted to pretend to be married, despite a father refusing to attend.
  • If a young unmarried mother had older, married and more financially secure parents or siblings, they may have asked them to raise the child “as their own”. This would hide their secret illegitimacy and protect both mother and child’s reputation.
  • Neighbours may have helped bring up a child. My own illegitimate Great-Grandmother was brought up by her neighbours. She didn’t realise her mother (an occasional visitor, called “Aunt Sissy”) was her mother until later in life – by which time “Aunt Sissy” had remarried and had other children.
  • In more extreme instances poor women may have decided that it would be best for both their child and themselves to leave the child – either at a foundling hospital or having the child adopted.
  • A child lives with their father and their mother is not present. Unmarried mother’s lost right’s over their child once they turned 7 years old. A wealthy father may have decided that they wanted to bring up the child (or send them to boarding school) and give them financial support

Of course, these are just a few examples and just as many people have complicated family structures now – so too did people in the past!

10 hints to help you discover illegitimate ancestors' father's names

What family historian doesn’t want to fill in that blank space on a birth record? Of course we ask ourselves, who is the father? Did they know about their child? Did they abandon both mother and child? Why?

Sometimes we may never find the answer to these questions – but we should always keep striving to try and answer them. We shouldn’t presume that it’s impossible. Read here my article detailing how I discovered the father of my illegitimate 3x Great-Grandfather.

Here’s my top tips for tracking down father’s identities:

1. Check Marriage Certificates

A father’s name might not be recorded on their birth but they may have named one on their marriage. Sometimes this name is made up, but not always. Sometimes it really is the father’s name and sometimes it’s a muddled version or a half truth. Don’t forget to check all marriages (many of our ancestors married more than once, after being widowed). Lastly, make a note of the occupation of the father. It might help you narrow down possibilities.​

2. Stalk The Neighbours

If you have a hint of a father’s identity (perhaps due to DNA or one of the other suggestions on this list) – then look at your ancestor’s childhood neighbours. This may mean using census, or for earlier ancestors, looking at other children baptised within your ancestors parish. Can you find that name anywhere amongst the other parishioners?

2. Bastard Wasn't Always a Swear Word

The Bastardy Act 1733 meant that man could be imprisoned until he coughed up funds for looking after a child or at least agreed to marry the mother of his child. This was not an Act born of altruism. There was a real risk that children born outside of wedlock would become a financial burden upon the parish. Of course, parishes were keen to avoid this. Unmarried mothers were legally obliged to inform the parish that they were expecting to deliver an illegitimate child. They would then be submitted for a bastardy examination, during which they would be asked to name the father of their child. That father would then be required to pay regular support to mother and child (a bastardy bond). Alternatively, they could pay the parish compensation. In reality, many of these examinations took place after a child was born. This practice slowly lessoned after 1834 with the introduction of the New Poor Law (the one that brought about the workhouses).

3. Follow The Money

Whenever money changes hands there’s normally a record. These records might lead to clues. For example, parish accounts might detail payments to an unmarried mother AND maybe they took the time to note that the alleged father was deceased or serving in the militia. You never know until you check. See here for more detail on the parish chest.

Similarly, check whether your illegitimate ancestor completed an apprenticeship. These had to be paid for in the form of an indenture. Although a father’s name might not be included on your ancestor’s apprenticeship papers, the name of whoever paid the indenture might be a clue to a father’s identity. Read the The National Archives guide here.

Lastly if your pregnant ancestor entered the workhouse there may be information recorded, particularly if a settlement record were required. See here for a more detailed look at workhouse records.

4. "Naughty" Ancestors Leave A Mark

I’m sure you can imagine lots of circumstances within which the birth of a child might result in activities at court. Failure to pay maintenance. A disputed father’s identity. Tragically, perhaps the conception of your ancestor was tied up with a more serious crime (assault, rape, fraud). Check petty and quarter sessions for information.

5. Read All About It

You just never know what you are going to find in a newspaper, court cases of all sorts, family disputes. I found my own pregnant ancestor got into an altercation with one of her neighbours. I later discovered that the baby she was carrying did not belong to her husband. Was that what the altercation was about? Were these named neighbours clues to a father’s identity? You can purchase a subscription to Find My Past or British Newspaper Archives (affiliate links) to explore an amazing collection of newspapers. Read my article here.

6. Track Mum's Movements

It sounds obvious and it is highly dependent on when your ancestor was born – but where was Mum about 9 months before she gave birth? Who was nearby? What was Mum doing?

7. Take A DNA Test

Cluster your results using colour coding to tie up each of your grandparents, then great grandparents. Is there a surname in your matches that keeps cropping up? One you can’t account for? Or do you have surnames in your matches tree that tie in with clues you’ve gained from trying the above steps? Please keep in mind you are more likely to have success with DNA with more recent illegitimate ancestors. DNA is diluted over the generations.

I recommend testing with Ancestry, purely because it has the largest database of test kits. You can purchase a kit here. Please note this is an affiliate link.

Don't Give Up

I hope, like Nick, you manage to track down the father’s of your illegitimate ancestors. But be prepared for some surprises along the way. Nick certainly found some! Please also note that it can take a long time to track down the identify of those illusive unnamed fathers. It’s not easy and definitely falls into the realms of more advanced genealogy. Services like my one-to-one tuition might be able to help you tackle these techniques in detail.

Further Reading

University of Cambridge, Supporting London’s Bastard Children 

I haven’t read this one yet but it is definitely on my must read list –

Evans, Tanya. “Unfortunate Objects”: Lone Mothers in Eighteenth-Century London. 2005

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