Brennan Family History

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Brennan Name Meaning

(predominantly southern) Anglicized form of Gaelic Ó Braonáin ‘descendant of Braonán’, a personal name from a diminutive of braon ‘moisture’, ‘drop’. Compare Breen. (predominantly northern) Anglicized form of Gaelic Ó Branáin ‘descendant of Branán’, a personal name meaning ‘little raven’ (see Brannigan).

Source: Dictionary of American Family Names ©2013, Oxford University Press

Similar surnames: Drennan, Greenan, Grennan, Bressan, Brenna, Grannan, Breihan, Brenton

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Brennan Ethnicity Estimate

What are the common regions with the Brennan name?

These results combine data from everyone in the AncestryDNA® database with the last name Brennan. The Ancestry® ethnicity regions shown are top five most common on average for these people.

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  • Ireland & Scotland


  • England & Wales


  • Germanic Europe


  • Eastern Europe & Russia


  • France


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Brennan Family Origin

Where is the Brennan family from?

Brennan Family Occupations

What did your Brennan ancestors do for a living?

In 1881, the most common Brennan occupation in the UK was Labourer. 8% of Brennan's were Labourers. A less common occupation for the Brennan family was Tailor. Labourer, Coal Miner and Housekeeper were the top 3 reported jobs worked by Brennan.

View Census data for Brennan | Data not to scale

  • Labourer

  • Coal Miner

  • Housekeeper

  • Tailor


Census records can tell you a lot of little known facts about your Brennan ancestors, such as occupation. Occupation can tell you about your ancestor's social and economic status.

Brennan Historical Records

What Brennan family records will you find?

Census Record

There are 378,000 census records available for the last name Brennan. Like a window into their day-to-day life, Brennan census records can tell you where and how your ancestors worked, their level of education, veteran status, and more.

Search 1891 UK census records for Brennan

Passenger List

There are 82,000 immigration records available for the last name Brennan. Passenger lists are your ticket to knowing when your ancestors arrived in the UK, and how they made the journey - from the ship name to ports of arrival and departure.

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Draft Card

There are 69,000 military records available for the last name Brennan. For the veterans among your Brennan ancestors, military collections provide insights into where and when they served, and even physical descriptions.

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You've only scratched the surface of Brennan family history.

Brennan Life Expectancy

What is the average Brennan lifespan?

Between 1940 and 2004, in the United States, Brennan life expectancy was at its lowest point in 1945, and highest in 2001. The average life expectancy for Brennan in 1940 was 40, and 74 in 2004.

View Social Security Death Index (SSDI) for Brennan

An unusually short lifespan might indicate that your Brennan ancestors lived in harsh conditions. A short lifespan might also indicate health problems that were once prevalent in your family. The SSDI is a searchable database of more than 70 million names. You can find birthdates, death dates, addresses and more.

Famous Brennan Family Ancestors

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