JM
James Mahoney — 1940 US Census Record
Model Tree available1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this James Mahoney across the 1920, 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed), with identified parents Rose — first a head (b.~1903), then head of a 7-person household.
Age 37
b. ~1903
Male
Head
Born: Illinois
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | Mahoney |
| Given Name | James |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 37 |
| Marital Status | Married |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago |
| 1935 Residence (County) | Cook |
| Additional Details | |
| Occupation | Lawyer |
| Industry | Street Railway |
| Class of Worker | PW |
| Hours Worked | 48 |
| Income (1939) | 2200 |
| Highest Grade | C-4 |
| 1935 Residence | Same place |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Occupation | Lawyer |
| Township / Ward | Chicago |
| Est. Birth Year | ~1903 |
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.
7 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to James | Age | Birth yr |
|---|---|---|---|---|
| Marie Mahoney | Spouse | — | 38 | ~1902 |
| James Mahoney | Son | — | 4 | ~1936 |
| James Mahoney | Head | — | 37 | ~1903 |
| Mary Byrne | Other | — | 65 | ~1875 |
| Patricia Mahoney | Daughter | — | 8 | ~1932 |
| Daniel Byrne | Other | — | 28 | ~1912 |
| Mary Mahoney | Daughter | — | 1 | ~1939 |
Census Appearances
1920
Cook, Illinois
Son, age 15
Cook, Illinois · implied b. ~1905 — 9 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Mahoney |
| Given Name | James |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 15 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Canada |
| Mother's Birthplace | New York |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1930
Cook, Illinois
Son, age 25
Cook, Illinois · implied b. ~1905 — 8 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Mahoney |
| Given Name | James A |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 25 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Canada |
| Mother's Birthplace | New York |
| Occupation | Lawyer |
| Industry | County Line |
| Class of Worker | W |
| Can Read/Write | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Cook-County, Illinois
Head, age 37
Cook-County, Illinois · implied b. ~1903 — 7 household members
| Surname | Mahoney |
| Given Name | James |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 37 |
| Marital Status | Married |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago |
| 1935 Residence (County) | Cook |
| Occupation | Lawyer |
| Industry | Street Railway |
| Class of Worker | PW |
| Hours Worked | 48 |
| Income (1939) | 2200 |
| Highest Grade | C-4 |
| 1935 Residence | Same place |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
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 James Mahoney across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: mother Rose Mahoney (~0.92 confidence). The pedigree spans 1 generation with 1 identified ancestor.
Show:
Gen 1
Parents
confidence ≈ 0.92
Mother
Rose Mahoney
b. ~1873
Source mother
● Household
· direct · ~0.92
This person
Anchor record
James Mahoney
Head · 1940 · age 37 · b. ~1903 · Illinois
★ You are viewing this record
Confirmed / household (~0.90+)
Probable / derived (~0.65–0.89)
Candidate (<0.65, unverified)
Original Census Page
1940 US Federal Census — Cook-County, Illinois
Open full size
1940 US Federal Census — Cook-County, Illinois
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-00992-00382)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Mae Gregory | 41 | Head | Book Binder | Michigan |
| 2 | Fred Hacker | 32 | Brother in law | Counter Man | Illinois |
| 3 | Lillian Hacker | 31 | Sister | — | Illinois |
| 4 | James Konis | 84 | Head | — | New York |
| 5 | Mary Konis | 80 | Wife | — | Illinois |
| 6 | Walter C Sahlin | 46 | Son in law | Salesman | Illinois |
| 7 | Kathryn Sahlin | 44 | Daughter | — | Illinois |
| 8 | Alfred Goetz | 62 | Head | Buyer | Germany |
| 9 | Mae Goetz | 53 | Wife | — | Illinois |
| 10 | Norma Hiela | 23 | Roomer | Stenographer | Minnesota |
| 11 | Walter Sturber | 41 | Head | Electrical Tester | Illinois |
| 12 | Edith Sturber | 35 | Wife | — | Illinois |
| 13 | James Mahoney THIS PERSON | 37 | Head | Lawyer | Illinois |
| 14 | Marie Mahoney | 38 | Wife | — | Illinois |
| 15 | Patricia Mahoney | 8 | Daughter | — | Illinois |
| 16 | James Mahoney | 4 | Son | — | Illinois |
| 17 | Mary K Mahoney | 1 | Daughter | — | Illinois |
| 18 | Mary Byrne | 65 | Mother in law | — | Ireland |
| 19 | Daniel Byrne | 28 | Brother in law | Fireman | Illinois |
| 20 | John Byrne | 39 | Head | Policeman | Illinois |
| 21 | Mary Byrne | 36 | Wife | — | Illinois |
| 22 | Lawrence Byrne | 14 | Son | — | Illinois |
| 23 | John Jr Byrne | 12 | Son | — | Illinois |
| 24 | Carol Ann Byrne | 3 | Daughter | — | Illinois |
| 25 | Emma Anderson | 58 | Head | — | Sweden |
| 26 | Clifford Anderson | 22 | Son | Clerk | Illinois |
| 27 | John G Patton | 28 | Head | Night Superintendent | Illinois |
| 28 | Helen Patton | 26 | Wife | — | Illinois |
| 29 | Otto Kamlow | 70 | Head | Metal Polisher | Germany |
| 30 | Bertha Kamlow | 69 | Wife | — | Wisconsin |
| 31 | Joseph Trotter | 49 | Head | Manager | Tennessee |
| 32 | Thelma Trotter | 44 | Wife | — | Germany |
| 33 | Lester Boe | 44 | Head | Second Vice President | Illinois |
| 34 | Pearl Boe | 44 | Wife | — | Illinois |
| 35 | Jens P Jensen | 52 | Head | Manager | Denmark |
| 36 | Paula Jensen | 50 | Wife | — | Denmark |
| 37 | Rudolph Urban | 51 | Head | Chauffeur | Illinois |
| 38 | Clara Urban | 49 | Wife | — | Illinois |
| 39 | Louise Urban | 14 | Daughter | — | Illinois |
| 40 | George Harathuin | 37 | Head | Accountant | Illinois |
Pedigree Summary
James
Gen 1 · 1 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)