How many John Cassidy census records do you have?

We have 5727 US Census records for John Cassidy, from 1900 to 1950, across 50 states, DC, and 1 territory.

What's in a John Cassidy census record?

You'll see John's age, birthplace, occupation, and relationship to the head of household — plus everyone else who lived in the same home. For 1940 and 1950 records, you can also view the original handwritten census page.

How do I use census records for family research?

Census records are a snapshot of a family every 10 years. You can follow John Cassidy's household over time — see when children appear, when people move states, and who's living together. YourRoots connects census data with Tree Matching and AI tools so you can build out your tree faster.

Are John Cassidy census records free?

Yes. All John Cassidy census records on YourRoots are free to search and view — no subscription required. We built our own index from the original federal census images.

Which census years and states cover John Cassidy?

We have John Cassidy records from the 1900 through 1950 US Federal Census, across 50 states, DC, and 1 territory. Use the year and state filters to narrow your results.

How do I find John Cassidy in the census?

Start by narrowing the year and state. If you know an approximate birth year, use the age column to match — census age minus the census year gives you a birth year estimate. Household members, birthplace, and occupation help confirm you have the right person.

What is the Model Tree for John Cassidy?

The Model Tree is YourRoots' unique feature that links a person across multiple census decades and reconstructs their likely family — parents, siblings, spouse, and children — based on household patterns. It turns isolated records into a connected family network.

Where does the census data come from?

All records originate from the US Federal Census microfilm digitized by NARA (National Archives and Records Administration). YourRoots re-indexed the original page images using modern AI, catching names and details that older transcriptions missed.

John Cassidy — US Census Records & Model Tree

We found 5727 free census records for John Cassidy across 6 census years (1900–1950), in 50 states, DC, and 1 territory and 761 counties. Each record includes our Model Tree — the same person linked across decades using machine learning, with per-link confidence scores.

John Cassidy Census Records by State & County

Records per state:

Census Record Search

First Name

Middle Name

Last Name (Required)

Census Year

State

Birth Year

Year Range

Birthplace

Age From

Age To

Exact match: Name Location Year

Alternate First Names (comma-separated)

Alternate Last Names (comma-separated)

County

Sex

Marital Status

Race

Relationship to Head

Occupation

Census Page ID

Family Members (in same household)

Search Records

Showing of 5727 records for John Cassidy US Census, ranked by Model Tree richness

No records match your filters.

Year	Name	Age	Location	Birthplace	Occupation	Relation
1940	John Cassidy	38	Will-County, Illinois	Illinois	Clerk	Head
1940	John P Cassidy	24	Essex-County, Massachusetts	Massachusetts	Fountain Man	Son
1940	John Patrick Cassidy	23	San-Francisco-County, California	California	Police Officer	Head
1940	John Cassidy	38	Darlington-County, South Carolina	South Carolina	Machinist	Head
1940	John F. Cassidy	27	Denver-County, Colorado	Colorado	Secretary	Son
1940	John B. Cassidy	38	Franklin-County, Ohio	Ohio	Clerk	Head
1940	John Cassidy	30	Hudson-County, New Jersey	New Jersey	Machinist	Son
1940	John Cassidy	23	Cuyahoga-County, Ohio	Ohio	Grinder	Son
1930	John J. Cassidy		Cook, Illinois	Illinois	Baggage	Head
1930	John Cassidy		New York, New York	New York	Chauffeur	Head
1940	John J. Cassidy	34	Essex-County, Massachusetts	Massachusetts	Owner Manager	Son
1940	John Cassidy	58	Queens-County, New York	New York	Auto Engineer	Head
1920	John Cassidy		Cook, Illinois	Illinois	Foreman	Head
1940	John S. Cassidy	61	Peoria-County, Illinois	England	Machinist	Head
1940	John H. Cassidy	45	Hennepin-County, Minnesota	Wisconsin	General Repair Man	Head
1940	John Cassidy	65	Kings-County, New York	Ireland	Retired	Head
1940	John Cassidy	56	New-York-County, New York	New Jersey	Porter	Head
1940	John M. Cassidy	53	Hudson-County, New Jersey	Scotland	Medical Doctor	Head
1940	John Cassidy	51	Beaver-County, Pennsylvania	Kentucky	Engineer	Head
1940	John D. Cassidy	71	Livingston-County, Illinois	Illinois	—	Head
1940	John E. Cassidy	71	Kings-County, New York	New York	—	Head
1930	John H Cassidy		Cobb, Georgia	Georgia	Laborer	Head
1940	John Cassidy	11	Philadelphia-County, Pennsylvania	SCOTLAND	—	Son
1940	John Cassidy	15	Mackinac-County, Michigan	Michigan	—	Son
1930	John Cassidy		Westchester, New York	Scotland	Superintendent	Head
1940	John Cassidy	10	Kings-County, New York	New York	—	Son
1930	John Cassidy		New York, New York	New York	Asst. Supt.	Son
1910	John F Cassidy		Middlesex, Massachusetts	Ireland	Laborer	Head
1920	John Cassidy		None, None	New York	—	Son
1930	John Cassidy		Hudson, New Jersey	New Jersey	Accountant	Son

Load More John Cassidy Census Records

About John Cassidy US Census Records & Model Tree

We've indexed 5727 free, proprietary US Census records for John Cassidy across 1900–1950, covering 50 states, DC, and 1 territory: Alabama, Alaska, Arizona, Arkansas, California, Colorado, Connecticut, Delaware, District of Columbia, Florida, Georgia, Hawaii, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Puerto Rico, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Vermont, Virginia, Washington, West Virginia, Wisconsin, Wyoming.

Each record includes our Model Tree — a longitudinal reconstruction that links the same person across census decades using machine learning (XGBoost record linkage). Every link carries a confidence score: Verified (≥0.99), Confirmed (≥0.95), or Linked (lower confidence). This tells you not just what the census says, but how reliably we've connected records across time.

Every record also shows the full household — who John lived with, their ages, birthplaces, and occupations. For 1940 and 1950 records, you can view the original handwritten census page from the National Archives.

How we build the Model Tree. YourRoots independently indexes US Census records from NARA microfilm and links persons across decades using XGBoost-based record linkage. Each link's confidence is a per-pair match score from the model. Household corroboration (co-residents appearing on the same census pages in multiple years) strengthens the signal. The Model Tree is not a family tree submitted by users — it's reconstructed from the census data itself.

Last updated: July 30, 2026

Frequently Asked Questions

: We have 5727 US Census records for John Cassidy, from 1900 to 1950, across 50 states, DC, and 1 territory.
: You'll see John's age, birthplace, occupation, and relationship to the head of household — plus everyone else who lived in the same home. For 1940 and 1950 records, you can also view the original handwritten census page.
: Census records are a snapshot of a family every 10 years. You can follow John Cassidy's household over time — see when children appear, when people move states, and who's living together. YourRoots connects census data with Tree Matching and AI tools so you can build out your tree faster.
: Yes. All John Cassidy census records on YourRoots are free to search and view — no subscription required. We built our own index from the original federal census images.
: We have John Cassidy records from the 1900 through 1950 US Federal Census, across 50 states, DC, and 1 territory. Use the year and state filters above to narrow your results.
: Start by narrowing the year and state. If you know an approximate birth year, use the age column to match — census age minus the census year gives you a birth year estimate. Household members, birthplace, and occupation help confirm you have the right person.
: The Model Tree is YourRoots' unique feature that links a person across multiple census decades and reconstructs their likely family — parents, siblings, spouse, and children — based on household patterns. It turns isolated records into a connected family network.
: All records originate from the US Federal Census microfilm digitized by NARA (National Archives and Records Administration). YourRoots re-indexed the original page images using modern AI, catching names and details that older transcriptions missed.