TC
Thomas Callahan — 1940 US Census Record
Model Tree available1940 United States Federal Census · Mercer-County, New Jersey
Our Model Tree links this Thomas Callahan across the 1920, 1930 and 1940 US Censuses in Mercer-County, New Jersey (XGBoost, ~Confirmed), with identified parents Thomas & Katherine — first a son (b.~1905), then head of a 4-person household.
Age 35
b. ~1905
Male
Son
Born: New Jersey
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Mercer-County, New Jersey |
| Surname | Callahan |
| Given Name | Thomas |
| Relationship to Head | son |
| Sex | M |
| Color / Race | White |
| Age | 35 |
| Marital Status | Single |
| Birthplace | New Jersey |
| 1935 Residence (City) | Trenton City |
| 1935 Residence (County) | Mercer |
| Additional Details | |
| Occupation | Steam Fitter |
| Industry | Plumbing |
| Class of Worker | PW |
| Hours Worked | 40 |
| Highest Grade | Hs 4 |
| 1935 Residence | Same house |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
| Occupation | Steam Fitter |
| Township / Ward | Trenton City |
| Est. Birth Year | ~1905 |
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.
4 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Thomas | Age | Birth yr |
|---|---|---|---|---|
| Thomas Callahan | Head | — | 60 | ~1880 |
| Thomas Callahan | Son | — | 35 | ~1905 |
| Joseph Callahan | Son | — | 31 | ~1909 |
| Katherine Callahan | Spouse | — | 56 | ~1884 |
Census Appearances
1920
Mercer, New …
Other, age 14
Mercer, New Jersey · implied b. ~1906 — 9 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Callahan |
| Given Name | Thomas |
| Relationship to Head | Boarder |
| Sex | M |
| Color / Race | White |
| Age | 14 |
| Marital Status | Single |
| Birthplace | New Jersey |
| Father's Birthplace | New Jersey |
| Mother's Birthplace | New Jersey |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
1930
Mercer, New …
Son, age 24
Mercer, New Jersey · implied b. ~1906 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Callahan |
| Given Name | Thomas J Jr |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 24 |
| Marital Status | Single |
| Birthplace | New Jersey |
| Father's Birthplace | New Jersey |
| Mother's Birthplace | New Jersey |
| Occupation | Apprentice |
| Industry | Plumbing |
| Class of Worker | W |
| Can Read/Write | Yes |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
1940
Mercer-County, New …
Son, age 35
Mercer-County, New Jersey · implied b. ~1905 — 4 household members
| Surname | Callahan |
| Given Name | Thomas |
| Relationship to Head | son |
| Sex | M |
| Color / Race | White |
| Age | 35 |
| Marital Status | Single |
| Birthplace | New Jersey |
| 1935 Residence (City) | Trenton City |
| 1935 Residence (County) | Mercer |
| Occupation | Steam Fitter |
| Industry | Plumbing |
| Class of Worker | PW |
| Hours Worked | 40 |
| Highest Grade | Hs 4 |
| 1935 Residence | Same house |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
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 Callahan across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father Thomas Callahan (~0.92 confidence) and mother Katherine Callahan (~0.92 confidence). The pedigree spans 1 generation with 2 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
Thomas Callahan
b. ~1879
Source father
● Household
· direct · ~0.92
Mother
Katherine Callahan
b. ~1884
Source mother
● Household
· direct · ~0.92
This person
Anchor record
Thomas Callahan
Son · 1940 · age 35 · b. ~1905 · New Jersey
★ You are viewing this record
Sibling
Joseph Callahan
Sibling · 1940 · age 31
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 — Mercer-County, New Jersey
Open full size
1940 US Federal Census — Mercer-County, New Jersey
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-02437-00364)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Lawrence Peterson | 48 | head | Bridge Engineer | Maine |
| 2 | Ethel Peterson | 48 | wife | — | Maine |
| 3 | Marjorie Peterson | 20 | daughter | — | New Jersey |
| 4 | Thomas Callahan | 60 | head | Passenger Conductor | New Jersey |
| 5 | Katherine Callahan | 56 | wife | — | New Jersey |
| 6 | Thomas Callahan THIS PERSON | 35 | son | Steam Fitter | New Jersey |
| 7 | Joseph Callahan | 31 | son | Patrolman | New Jersey |
| 8 | Hugh Wyrough | 48 | head | Mechanical Engineer | Pennsylvania |
| 9 | Anne Wyrough | 44 | wife | — | Pennsylvania |
| 10 | Eleanor A. B. Wyrough | 20 | daughter | — | Pennsylvania |
| 11 | Richard Wyrough | 12 | son | — | New Jersey |
| 12 | William @ Morgan | 53 | head | Investigator | New York |
| 13 | Henrietta Morgan | 43 | wife | — | Pennsylvania |
| 14 | William Jr. Morgan | 8 | son | — | New Jersey |
| 15 | Aron Farkas | 61 | head | — | Hungary |
| 16 | Bertha Farkas | 59 | wife | — | Hungary |
| 17 | Dorothy Farkas | 26 | daughter | Manager | New Jersey |
| 18 | Howard Thomas | 52 | head | Partner | New Jersey |
| 19 | Lillie Thomas | 58 | wife | — | New Jersey |
| 20 | Joseph Kessler | 32 | son-in-law | Proprietor | New Jersey |
| 21 | Ethel Kessler | 32 | daughter | — | New Jersey |
| 22 | William Ruth | 42 | head | Executive Secretary | New York |
| 23 | Frances @ Ruth | 42 | wife | — | New York |
| 24 | Dorothy Ruth | 16 | daughter | — | New York |
| 25 | Mary Ruth | 12 | daughter | — | New York |
| 26 | John Kirkpatrick | 54 | head | Latin Teacher | New Jersey |
| 27 | Mary Kirkpatrick | 55 | wife | — | Pennsylvania |
| 28 | Anthony @ Invidiatu | 35 | head | Salesman | Italy |
| 29 | Jennie Invidiatu | 40 | wife | History Teacher | New Jersey |
| 30 | Robert @ Blakeslee | 42 | head | Secretary And Chief Engineer | Connecticut |
| 31 | Barbara Blakeslee | 19 | daughter | — | Connecticut |
| 32 | Virginia Blakeslee | 15 | daughter | — | Connecticut |
| 33 | Ethel @ Clifford | 55 | maid | Maid | New Jersey |
| 34 | William @ Hartman | 42 | head | Principal Clerk | New Jersey |
| 35 | Mabel Hartman | 42 | wife | — | New York |
| 36 | Patience Hartman | 13 | daughter | — | New Jersey |
| 37 | William Hartman | 9 | son | — | New Jersey |
| 38 | Emma | 45 | sister | Visiting Teacher | New Jersey |
| 39 | Rebecca | 85 | Aunt | — | New Jersey |
| 40 | Charles Gano | 70 | head | Partner Optometrist | New Jersey |
Pedigree Summary
Thomas + 1 sibling
Gen 1 · 2 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)