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Thomas Leonard — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Middlesex-County, Massachusetts
Our Model Tree links this Thomas Leonard across the 1920, 1930 and 1940 US Censuses in Middlesex-County, Massachusetts (XGBoost, ~Confirmed) — first a head (b.~1879), then head of a 3-person household.
Age 61
b. ~1879
Male
Head
Born: Massachusetts
Widowed
1940 Census Record Details
| Census Year | 1940 |
| Location | Middlesex-County, Massachusetts |
| Surname | Leonard |
| Given Name | Thomas H |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 61 |
| Marital Status | Widowed |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston |
| 1935 Residence (County) | Suffolk |
| Additional Details | |
| Occupation | Inspector |
| Industry | Water Department |
| Class of Worker | GW |
| Hours Worked | 40 |
| Income (1939) | 1900 |
| Highest Grade | 8 |
| 1935 Residence | Massachusetts |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
| Occupation | Inspector |
| Township / Ward | Malden City |
| Est. Birth Year | ~1879 |
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.
3 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Thomas | Age | Birth yr |
|---|---|---|---|---|
| Daniel Kelleher | Other | — | 25 | ~1915 |
| Grace Robertson | Daughter | — | 2 | ~1938 |
| Thomas Leonard | Head | — | 61 | ~1879 |
Census Appearances
1920
Middlesex, Massachusetts
Head, age 39
Middlesex, Massachusetts · implied b. ~1881 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Leonard |
| Given Name | Thomas |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 39 |
| Marital Status | Married |
| Birthplace | Massachusetts |
| Father's Birthplace | Massachusetts |
| Mother's Birthplace | Ireland |
| Occupation | Foreman |
| Industry | Construction |
| Class of Worker | W |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Home Owned/Rented | R |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1930
Middlesex, Massachusetts
Head, age 49
Middlesex, Massachusetts · implied b. ~1881
●
Primary link
· ~Confirmed · 1 source
XGBoost
| Surname | Leonard |
| Given Name | Thomas H. |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 49 |
| Marital Status | Married |
| Birthplace | Massachusetts |
| Age at First Marriage | 25 |
| Father's Birthplace | Irish Free State |
| Mother's Birthplace | Irish Free State |
| Occupation | Meter reader |
| Industry | Water Dept. |
| Class of Worker | W |
| Can Read/Write | Yes |
| Home Owned/Rented | O |
| Home Value / Rent | 700 |
| Radio Set | R |
| Veteran | No |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1940
Middlesex-County, Massachusetts
Head, age 61
Middlesex-County, Massachusetts · implied b. ~1879 — 3 household members
| Surname | Leonard |
| Given Name | Thomas H |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 61 |
| Marital Status | Widowed |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston |
| 1935 Residence (County) | Suffolk |
| Occupation | Inspector |
| Industry | Water Department |
| Class of Worker | GW |
| Hours Worked | 40 |
| Income (1939) | 1900 |
| Highest Grade | 8 |
| 1935 Residence | Massachusetts |
| 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 Thomas Leonard across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage.
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This person
Anchor record
Thomas Leonard
Head · 1940 · age 61 · b. ~1879 · Massachusetts
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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
4 people indexed on this census page (nara:1940:m-t0627-01609-00340)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 2 | Thomas H Leonard THIS PERSON | 61 | Head | Inspector | Massachusetts |
| 5 | Grace E Robertson | 2 | Daughter | — | Massachusetts |
| 8 | Daniel Kelleher | 25 | Brother-in-law | Shipper | Massachusetts |
| 11 | Jeremiah F White | 42 | Head | Machinist | Massachusetts |
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)