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Joseph Brennan — 1940 US Census Record
Model Tree available1940 United States Federal Census · Middlesex-County, Massachusetts
Our Model Tree links this Joseph Brennan across the 1910, 1920, 1930 and 1940 US Censuses in Middlesex-County, Massachusetts (XGBoost, ~Confirmed), with identified parents John & Michael — first a son (b.~1910), then head of a 6-person household.
Age 30
b. ~1910
Male
Son
Born: Massachusetts
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Middlesex-County, Massachusetts |
| Surname | Brennan |
| Given Name | Joseph |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 30 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Cambridge |
| 1935 Residence (County) | Middlesex |
| Additional Details | |
| Occupation | General worker |
| Industry | Wholesale meat |
| Class of Worker | PW |
| Hours Worked | 4 |
| Income (1939) | 1400 |
| Highest Grade | No 8 |
| 1935 Residence | Same place |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
| Occupation | General Worker |
| Township / Ward | Cambridge |
| Est. Birth Year | ~1910 |
Household Members
Census records only state relationship to the household head.
Pairwise kinship is derived (~90–95% accurate), not recorded.
Step/blended families and boarders can break it.
6 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Joseph | Age | Birth yr |
|---|---|---|---|---|
| Mary Brennan | Daughter | — | 35 | ~1905 |
| Agnes Brennan | Daughter | — | 26 | ~1914 |
| William Brennan | Son | — | 33 | ~1907 |
| John Brennan | Head | — | 65 | ~1875 |
| Joseph Brennan | Son | — | 30 | ~1910 |
| Helena Brennan | Son | — | 40 | ~1900 |
Census Appearances
1910
Worcester, Massachusetts
Son, age 1
Worcester, Massachusetts · implied b. ~1909 — 8 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Brennan |
| Given Name | Joseph |
| Relationship to Head | son |
| Sex | M |
| Color / Race | White |
| Age | 1 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Ire. English |
| Mother's Birthplace | Massachusetts |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1920
Worcester, Massachusetts
Son, age 10
Worcester, Massachusetts · implied b. ~1910 — 9 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Brennan |
| Given Name | Joseph |
| Relationship to Head | son |
| Sex | M |
| Color / Race | White |
| Age | 10 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Massachusetts |
| Occupation | none |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1930
Worcester, Massachusetts
Son, age 20
Worcester, Massachusetts · implied b. ~1910 — 8 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Brennan |
| Given Name | Joseph F |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 20 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Can Read/Write | Yes |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1940
Middlesex-County, Massachusetts
Son, age 30
Middlesex-County, Massachusetts · implied b. ~1910 — 6 household members
| Surname | Brennan |
| Given Name | Joseph |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 30 |
| Marital Status | Single |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Cambridge |
| 1935 Residence (County) | Middlesex |
| Occupation | General worker |
| Industry | Wholesale meat |
| Class of Worker | PW |
| Hours Worked | 4 |
| Income (1939) | 1400 |
| Highest Grade | No 8 |
| 1935 Residence | Same place |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
Model Tree
An inferred pedigree reconstructed from census links — up to 4 generations within the 1900–1950 window. Closer generations are built from household co-residence; deeper ones are bridged by following a relative to their own childhood census. Confidence compounds and weakens with each generation.
Our Model Tree links Joseph Brennan across 4 US Census years (1910, 1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father John Brennan (~0.92 confidence) and father Michael Brennan (~0.92 confidence) and father Michael Brennan (~0.92 confidence) and mother Mary Brennan (~0.92 confidence) and mother Mary Brennan (~0.92 confidence). The pedigree spans 1 generation with 5 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
John Brennan
b. ~1875
Source father
● Household
· direct · ~0.92
Father
Michael Brennan
b. ~1875
Source father
● Household
· direct · ~0.92
Father
Michael Brennan
b. ~1876
Source father
● Household
· direct · ~0.92
Mother
Mary Brennan
b. ~1873
Source mother
● Household
· direct · ~0.92
Mother
Mary Brennan
b. ~1878
Source mother
● Household
· direct · ~0.92
This person
Anchor record
Joseph Brennan
Son · 1940 · age 30 · b. ~1910 · Massachusetts
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Sibling
Agnes Brennan
Sibling · 1940 · age 26
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Helena Brennan
Sibling · 1940 · age 40
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
William Brennan
Sibling · 1940 · age 33
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Mary Brennan
Sibling · 1940 · age 35
Source co-child of head (derived)
● Co-child · derived · ~0.88
Confirmed / household (~0.90+)
Probable / derived (~0.65–0.89)
Candidate (<0.65, unverified)
Original Census Page
1940 US Federal Census — Middlesex-County, Massachusetts
Open full size
1940 US Federal Census — Middlesex-County, Massachusetts
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01683-00023)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Angelo Nardone | 30 | Head | Laborer | Massachusetts |
| 2 | Dorothy Nardone | 29 | Wife | Worker | Massachusetts |
| 3 | Clement Pawloski | 44 | Head | Maker | Russia |
| 4 | Eva Pawloski | 31 | Wife | — | Russia |
| 5 | William Pawloski | 14 | Son | — | New Jersey |
| 6 | Doris Pawloski | 12 | Daughter | — | New Jersey |
| 7 | James Doyle | 27 | Partner | Worker | Russia |
| 8 | Frederick O'Connell | 24 | Head | Mechanic | Massachusetts |
| 9 | Marie M. O'Connell | 23 | Wife | — | Massachusetts |
| 10 | Frederick Jr. O'Connell | 3 | Son | — | Massachusetts |
| 11 | Daniel O'Connell | 1 | Son | — | Massachusetts |
| 12 | Helen M. O'Hearn | 49 | Head | Bookkeeper | Massachusetts |
| 13 | Joseph Piercy | 74 | Head | — | Italy |
| 14 | Michael A. Piercy | 60 | Son | Elevator Operator | Italy |
| 15 | John James Piercy | 53 | Son | — | Massachusetts |
| 16 | Alfred Baratta | 33 | Head | Compositor | Massachusetts |
| 17 | Angeline Baratta | 29 | Wife | Stitching | Massachusetts |
| 18 | John Brennan | 65 | Head | — | Eire |
| 19 | Helena Brennan | 40 | Son | Laborer | Eire |
| 20 | Mary Brennan | 35 | Daughter | Waitress | Massachusetts |
| 21 | William Brennan | 33 | Son | Asphalt Worker | Massachusetts |
| 22 | Agnes Brennan | 26 | Daughter | Teacher | Massachusetts |
| 23 | Joseph Brennan THIS PERSON | 30 | Son | General Worker | Massachusetts |
| 24 | Joseph Mc. Leroy | 47 | Head | Attendant | Portugal |
| 25 | Anne Leroy | 40 | Wife | — | Massachusetts |
| 26 | Eleanor Leroy | 13 | Daughter | — | Massachusetts |
| 27 | Wendell Leroy | 7 | Son | — | Massachusetts |
| 28 | Earl F. Smith | 25 | Head | Porter | New Hampshire |
| 29 | Iva Smith | 23 | Wife | — | Maine |
| 30 | Earl Jr. Smith | 0 | Son | — | Massachusetts |
| 31 | Chester Mcmackin | 28 | Head | Oven Man | Maine |
| 32 | Helen Mcmackin | 23 | Wife | Roll Maker | Massachusetts |
| 33 | Ruth Mcmackin | 4 | Daughter | — | Massachusetts |
| 34 | Chester Jr. Mcmackin | 2 | Son | — | Massachusetts |
| 35 | Arthur B. Cramton | 61 | Head | Operator | Vermont |
| 36 | Peter Paul Stropey | 63 | Lodge | Coppersmith | Poland |
| 37 | Charles A. Rego | 38 | Lodge | Clerk | Portugal |
| 38 | Arthur H. Silva | 33 | Lodge | Plumber | Massachusetts |
| 39 | Margaret A. Cooney | 60 | Lodge | — | Newfoundland |
| 40 | Salvatore Agrello | 61 | Lodge | Laborer | Italy |
Pedigree Summary
Joseph + 4 siblings
Gen 1 · 5 parents
~0.92
Max depth 4 (1900–1950 window)
About This Record & Model Tree
This record was independently indexed by YourRoots from the 1940 United States Federal Census (NARA). Our Model Tree links this person across census decades using XGBoost-based record linkage, with per-link confidence scores. Household corroboration strengthens the signal when co-residents appear on the same census pages in multiple years.
Source: National Archives and Records Administration (NARA)