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 John & Mary — first a head (b.~1911), then head of a 5-person household.
Age 29
b. ~1911
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 | 29 |
| Marital Status | Married |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Additional Details | |
| Occupation | Off Set Press |
| Industry | Map Company |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 3000 |
| Highest Grade | H 4 |
| 1935 Residence | Same place |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Occupation | Off Set Press |
| Township / Ward | Chicago City |
| Est. Birth Year | ~1911 |
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.
5 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to James | Age | Birth yr |
|---|---|---|---|---|
| Mary Mahoney | Daughter | — | ~1940 | |
| Edward Mahoney | Son | — | 6 | ~1934 |
| James Mahoney | Head | — | 29 | ~1911 |
| Helen Mahoney | Spouse | — | 29 | ~1911 |
| James Mahoney | Son | — | 7 | ~1933 |
Census Appearances
1920
Cook, Illinois
Son, age 9
Cook, Illinois · implied b. ~1911 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Mahoney |
| Given Name | James |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 9 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Illinois |
| Mother's Birthplace | Illinois |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1930
Cook, Illinois
Son, age 19
Cook, Illinois · implied b. ~1911 — 2 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Mahoney |
| Given Name | James |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 19 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Illinois |
| Mother's Birthplace | Illinois |
| Occupation | Salesman |
| Industry | Commercial |
| Class of Worker | W |
| Can Read/Write | Yes |
| Veteran | No |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Cook-County, Illinois
Head, age 29
Cook-County, Illinois · implied b. ~1911 — 5 household members
| Surname | Mahoney |
| Given Name | James |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 29 |
| Marital Status | Married |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Occupation | Off Set Press |
| Industry | Map Company |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 3000 |
| Highest Grade | H 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: father John Mahoney (~0.92 confidence) and mother Mary Mahoney (~0.92 confidence) and mother Ella Mahoney (~0.92 confidence). The pedigree spans 1 generation with 3 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
John Mahoney
b. ~1877
Source father
● Household
· direct · ~0.92
Mother
Mary Mahoney
b. ~1879
Source mother
● Household
· direct · ~0.92
Mother
Ella Mahoney
b. ~1885
Source mother
● Household
· direct · ~0.92
This person
Anchor record
James Mahoney
Head · 1940 · age 29 · b. ~1911 · 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-t0627-01016-00681)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | John Borgeson | 57 | Head | Clerk-Office | Illinois |
| 42 | Lawrence Cook | 57 | Head | Maintenance | Indiana |
| 43 | Freda Cook | 41 | Wife | — | Indiana |
| 44 | Patrick Hoban | 52 | Head | Motorman | Free State Ireland |
| 45 | Sarah Hoban | 52 | Wife | — | Free State Ireland |
| 46 | Raymond Hoban | 26 | Son | Shipping Clerk | Illinois |
| 47 | John Hoban | 16 | Son | — | Illinois |
| 48 | George E Thyer | 46 | Head | Purchasing Agent | Illinois |
| 49 | Inez Thyer | 46 | Wife | — | Illinois |
| 50 | George Jr Thyer | 22 | Son | Clerk | Illinois |
| 51 | Warren E Thyer | 16 | Son | — | Illinois |
| 52 | William Schultz | 54 | Head | Superintendent | Illinois |
| 53 | Florence Schultz | 50 | Wife | — | Illinois |
| 54 | William Swanson | 61 | Head | Superintendent | Illinois |
| 55 | Julia E Swanson | 60 | Wife | — | Wisconsin |
| 56 | Nicolas Geishecker | 49 | Head | Policeman | Illinois |
| 57 | Abbie Geishecker | 48 | Wife | — | Illinois |
| 58 | Dorothy Geishecker | 16 | Daughter | — | Illinois |
| 59 | Mary Geishecker | 57 | Sister | — | Illinois |
| 60 | Adam Beuler | 53 | Head | Plasterer | Illinois |
| 61 | Alma Beuler | 47 | Wife | — | Missouri |
| 62 | Eileen Beuler | 17 | Daughter | — | Illinois |
| 63 | Pearl Beuler | 15 | Daughter | — | Illinois |
| 64 | Arnold Hall | 34 | Head | Manager | Illinois |
| 65 | Ruth Hall | 34 | Wife | Secretary | Illinois |
| 66 | Robert Hall | 4 | Son | — | Illinois |
| 67 | Sophia Hall | 65 | Mother | — | Illinois |
| 68 | Steve Rozemezak | 57 | Head | Yard Man | Poland |
| 69 | Rose Rozemezak | 50 | Wife | — | New York |
| 70 | Harold Rozemezak | 21 | Son | Repair Man | Illinois |
| 71 | Alex Rozemezak | 46 | Brother | Handy Man | Poland |
| 72 | Irene Poledna | 25 | Daughter | Packer | Illinois |
| 73 | Joseph Poledna | 28 | Son-in-law | Press Marker | Illinois |
| 74 | James Mahoney THIS PERSON | 29 | Head | Off Set Press | Illinois |
| 75 | Helen Mahoney | 29 | Wife | — | Illinois |
| 76 | James L Mahoney | 7 | Son | — | Illinois |
| 77 | Edward Mahoney | 6 | Son | — | Illinois |
| 78 | Mary Mahoney | 0 | Daughter | — | Illinois |
| 79 | Daniel Rozemezak | 27 | Head | Window Trimmer | Illinois |
| 80 | Ann Rozemezak | 25 | Wife | — | Illinois |
Pedigree Summary
James
Gen 1 · 3 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)