Great Fire of London Genealogy: Rebuilding Your Family History After 1666

That last sentence is where your research problem starts. It is also where the answer lives.

Great Fire of London: What actually burned

Roughly 13,200 houses went. Eighty-seven parish churches. Old St Paul’s Cathedral, the Royal Exchange, much of Guildhall. The scale of it is genuinely hard to picture, because we are talking about most of a walled medieval city gone inside a week.

But notice what that list is. It is a list of buildings.

Parish records lived in parish chests, and a chest could be carried. Some clerks and churchwardens got their registers out ahead of the flames. Some did not, and those registers are gone. There is no single rule here, which is exactly why the blanket assumption is so costly. Check your parish rather than assume for all of them.

And plenty of London was never touched. The fire had edges. Parishes east of the worst of it, the parishes beyond the walls, Southwark across the river, Westminster off to the west. If your ancestors lived in any of those in 1666, the fire is background noise in their story rather than the story itself.

Check out the dedicated page to London records including substitute records for those records actually lost as a result of the Great Fire of London.  Click HERE for the US version and HERE for the UK version.

Great Fire of London: Start with the parish

Before you look for a single record, work out which London parish your ancestor was in during 1666. Everything else follows from that.

This is fiddly work. The City had a great many small parishes packed into a very small area, and a street could sit on a boundary, houses on one side in one parish and houses opposite in another. Use a parish map of pre-fire London, and note the neighbouring parishes as well as your own. You will need them.

Then ask the useful question. Did that parish burn, and if it did, what happened to its paperwork and its people?

Great Fire of London: Parish registers, before and after

Parish registers are still your foundation. Baptisms, marriages, burials. Where a City parish register survives across 1666, you sometimes get an extraordinary thing: the same clerk’s handwriting carrying straight on through the disaster, burials thinning out as the parish empties, then a slow return of baptisms years later as families move back into rebuilt houses.

Where the register is lost or has a gap, do not stop. Bishop’s transcripts may exist for some parishes and periods, though London survival is patchy. Printed editions of City registers were also published by antiquarian societies in the nineteenth and early twentieth centuries, some made from originals that have since deteriorated.

Here is the trap. Fewer churches were rebuilt than had been destroyed, and parishes were united. Your parish may have kept its name on paper while its records were physically kept, and later catalogued, under the surviving partner parish. Researchers hunt for a register under the burned parish’s name, find nothing, and conclude it was destroyed. Often it was simply filed elsewhere.

Great Fire of London: Hearth tax, the household snapshot

The hearth tax assessments of the 1660s are one of the closest things we have to a household census of pre-fire London. They list occupiers by parish and by street, with the number of hearths in each dwelling, which also gives you a rough sense of how well or poorly the family was living.

Use them as a fixed point. A hearth tax entry places your named ancestor in a specific parish and often a specific street shortly before the fire. That is the “before” photograph. Everything you do afterwards is looking for the “after.”

Survival varies, so check what exists for your parish rather than assuming a full run.

Great Fire of London: The Fire Court and why it matters more than you would think

After the fire, Parliament created a special court to sort out the mess of rebuilding. Landlords, tenants, leases, who pays, who rebuilds, who is released from a lease on a house that no longer exists. The judges heard cases quickly and their decrees were binding.

For genealogists these records are gold, and they are badly underused. Property disputes generate names. The person bringing the case, obviously, and then relatives, executors, widows, previous tenants, neighbours giving evidence about who lived where. A Fire Court case can hand you a relationship that no parish register ever recorded, because a register records an event while a property dispute records a family arguing about who is entitled to what.

The London Archives, which you may still know as the London Metropolitan Archives, holds Fire Court material. Guildhall Library holds extensive collections on the Great Fire and City history more broadly, including printed and manuscript sources that often fill gaps for individual parishes.

Great Fire of London: A worked example, and I want to be clear this one is invented

The family below is hypothetical. I made them up to show the method. Their records do not exist and you will not find them.

Say your ancestor is a cooper named Edward Hale, and a hearth tax assessment puts him in a City parish east of St Paul’s with three hearths in 1666. His parish church burns. There is no burial for him, no burial for his wife, and the register goes quiet.

The instinct is to say the records burned. Try the other reading. Look at the parishes physically adjacent to his, and at the parishes just outside the walls. Search their registers from 1667 forward for the surname. A baptism turns up in a neighbouring parish in 1669 for a child of Edward and Mary Hale.

Then go to the property records. A Fire Court case about the rebuilding of his old leasehold names the widow Mary Hale and a brother acting for her, which tells you Edward died between 1666 and the hearing, and gives you a sibling you did not know existed. St Andrew Hubbard in Eastcheap is one real example of a church that was never rebuilt, its parish united with St Mary at Hill afterwards, and that is exactly the kind of pairing that hides a family from a careless search.

Invented family, real method.

Great Fire of London:  Following people who walked away

Not everyone who left came back. Rebuilding was expensive and slow, and a tradesman who lost his premises and his stock had every reason to set up somewhere cheaper.

So widen out. The suburbs first, Southwark and Stepney and Clerkenwell, then the counties where the family had trade or kin connections. For some families, overseas entirely, because the years after 1666 sit in the middle of a period of English emigration to the colonies. A London family that vanishes in 1666 and surfaces in a Kent parish or a Virginia county record is a common enough pattern that it is worth testing before you give up.

Great Fire of London: The part I actually want you to do

Identify your ancestor’s London parish in 1666. Write it down, and write down the parishes on either side of it while you are at it. Then put the parish registers and hearth tax records next to the Fire Court, property and post-fire parish records and see where the family goes.

It takes an afternoon to set up and it can undo a brick wall you have been staring at for years. I am asking you to do it because the assumption that everything burned is doing real damage to real research, and it is the kind of assumption nobody ever goes back and checks.

Three hundred and sixty years on, somebody in your family carried what they could out through a gate and slept in a field. Somewhere in the paperwork of what happened next, they wrote their name.

* * *

Author’s Note: I want to be transparent that this content – Great Fire of London Genealogy: Rebuilding Your Family History After 1666 – was created in part with the help of an artificial intelligence (AI) language model – Claude Opus 5. The AI assisted in generating an early draft of the content, but every paragraph was subsequently reviewed, edited, and refined by me. The final content is the result of extensive human curation and creativity. I am proud to present this work and assure readers that while AI was a tool in the process, the story, style, and substance have been carefully shaped by the author.