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Origins of the Brennan surname

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About the Brennans

We have a total number of 103796 records for people with the last name Brennan.

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I’ve managed to trace back to the mid-1500s! I can’t believe it! Utterly engrossing and I have uncovered some quite moving and heartbreaking stories attached to various ancestors. You don’t need any qualifications to start - just time patience, and some information.

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Delve deeper into the Brennan family's history

Where do most Brennans live?

In 1921, most Brennans lived in London.

Census records trace your ancestors through each generation, so you can follow where your relatives lived through each decade.

Interesting facts about Brennans

How common is your surname?

767th most common surname in the UK

We have 32,600 records for the Brennan surname. The oldest one dates back to 1820.

Who were Brennans most likely to marry?




Our Marriage record sets tell us which families married Brennans.

What are the most common Brennan first names?

  • John
  • James
  • Mary
  • Margaret

Our birth record sets tell us the names of Brennan family members

Common jobs for Brennans

Men and women often performed different types of jobs, so these are displayed by gender to maintain their historical accuracy.

Common Female occupations for Brennans in 1921
Cotton Weaver






Domestic Servant




Common Male occupations for Brennans in 1921
General Labourer


Dock Labourer


Coal Miner


Coal Miner Hewer


Semiskilled Chauffeurs And Drivers


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Census records provide incredible detail on names, ages, marital statuses, occupations and more.

We found over 80,000 family trees with the Brennan surname

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