JM
John Mahoney — 1940 US Census Record
Linked across censuses1940 United States Federal Census · St.-Louis-City-County, Missouri
Our Model Tree links this John Mahoney across the 1920, 1930 and 1940 US Censuses in St.-Louis-City-County, Missouri (XGBoost, ~Confirmed) — first a head (b.~1875), then head of a 3-person household.
Age 65
b. ~1875
Male
Head
Born: Ireland
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | St.-Louis-City-County, Missouri |
| Surname | Mahoney |
| Given Name | John |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 65 |
| Marital Status | Married |
| Birthplace | Ireland |
| 1935 Residence (City) | St Louis |
| 1935 Residence (County) | St. Louis City |
| Naturalization Status | Naturalized |
| Additional Details | |
| Occupation | motorman |
| Industry | public service |
| Class of Worker | PW |
| Income (1939) | 1097 |
| Highest Grade | No 6 |
| 1935 Residence | Same house |
| Birth Country | Ireland |
| Birthplace (normalized) | ireland |
| Occupation | Motorman |
| Township / Ward | St Louis |
| Est. Birth Year | ~1875 |
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 John | Age | Birth yr |
|---|---|---|---|---|
| John Mahoney | Head | — | 65 | ~1875 |
| Francis Mahoney | Son | — | 30 | ~1910 |
| Mary Mahoney | Spouse | — | 64 | ~1876 |
Census Appearances
1920
St Louis, …
Head, age 44
St Louis, Missouri · implied b. ~1876 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Mahoney |
| Given Name | John |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 44 |
| Marital Status | Married |
| Birthplace | Ireland |
| Year of Immigration | 1887 |
| Naturalization Status | Naturalized |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Occupation | none |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Mother Tongue | English |
| Home Owned/Rented | O |
| Home Free/Mortgaged | F |
| Birth Country | Ireland |
| Year of Naturalization | 1911 |
| Birthplace (normalized) | ireland |
1930
St Louis, …
Head, age 53
St Louis, Missouri · implied b. ~1877 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Mahoney |
| Given Name | John |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 53 |
| Marital Status | Married |
| Birthplace | Ireland |
| Naturalization Status | Naturalized |
| Year of Immigration | 1898 |
| Age at First Marriage | 32 |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Occupation | Waiter |
| Industry | Public Res |
| Class of Worker | W |
| Can Read/Write | Yes |
| Mother Tongue | English |
| Home Owned/Rented | O |
| Home Value / Rent | 7500 |
| Radio Set | R |
| Veteran | No |
| Birth Country | Ireland |
| Birthplace (normalized) | ireland |
1940
St.-Louis-City-County, Missouri
Head, age 65
St.-Louis-City-County, Missouri · implied b. ~1875 — 3 household members
| Surname | Mahoney |
| Given Name | John |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 65 |
| Marital Status | Married |
| Birthplace | Ireland |
| 1935 Residence (City) | St Louis |
| 1935 Residence (County) | St. Louis City |
| Naturalization Status | Naturalized |
| Occupation | motorman |
| Industry | public service |
| Class of Worker | PW |
| Income (1939) | 1097 |
| Highest Grade | No 6 |
| 1935 Residence | Same house |
| Birth Country | Ireland |
| Birthplace (normalized) | ireland |
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 John Mahoney across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
John Mahoney
Head · 1940 · age 65 · b. ~1875 · Missouri
★ 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 — St.-Louis-City-County, Missouri
Open full size
1940 US Federal Census — St.-Louis-City-County, Missouri
Page Contents
39 people indexed on this census page (nara:1940:m-t0627-02205-00932)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Mary Mancstar | 60 | Lodger | — | Yugoslavia |
| 3 | Fred Helm | 49 | Head | Marker | Missouri |
| 4 | Flora Helm | 44 | Wife | — | Missouri |
| 5 | Benjamin Withore | 48 | Head | Detective | Missouri |
| 6 | Bertha Withore | 41 | Wife | — | Missouri |
| 7 | Lester Withore | 22 | Son | Police Man | Missouri |
| 8 | Elmer Withore | 20 | Son | Comptometer | Missouri |
| 9 | Margaret Withore | 18 | Daughter | — | Missouri |
| 10 | Mildred Withore | 13 | Daughter | — | Missouri |
| 11 | Andrew Withore | 4 | Son | — | Missouri |
| 12 | Andrew O'Brien | 47 | Head | Laborer | Ireland |
| 13 | Ellen O'Brien | 34 | Wife | — | Ireland |
| 14 | Mary Ellen O'Brien | 12 | Daughter | — | Missouri |
| 15 | Katherine O'Brien | 10 | Daughter | — | Missouri |
| 16 | Margaret O'Brien | 8 | Daughter | — | Missouri |
| 17 | Annmae O'Brien | 7 | Daughter | — | Missouri |
| 18 | Andrew O'Brien | 5 | Son | — | Missouri |
| 19 | Thomas Hickey | 33 | Brother-in-law | Laborer | Ireland |
| 20 | Edward Buckley | 57 | Head | Laborer | Ireland |
| 21 | Julian Buckley | 47 | Wife | Housemaid | Ireland |
| 22 | Edward Buckley | 20 | Son | New Worker | Missouri |
| 23 | Andrew Buckley | 18 | Son | Curb Service Waiter | Missouri |
| 24 | John Buckley | 16 | Son | — | Missouri |
| 25 | Mary Buckley | 14 | Daughter | — | Missouri |
| 26 | Timothy Buckley | 12 | Son | — | Missouri |
| 27 | Cornelius Riordan | 35 | Head | All Around Clerk | Ireland |
| 28 | Mary Riordan | 36 | Wife | — | Ireland |
| 29 | Cornelius Riordan | 10 | Son | — | Missouri |
| 30 | John Riordan | 7 | Son | — | Missouri |
| 31 | Mary Ann Riordan | 1 | Daughter | — | Missouri |
| 32 | Robert Backer | 53 | Head | Supervisor | Missouri |
| 33 | Frances Backer | 55 | Wife | — | Missouri |
| 34 | Howard Backer | 23 | Son | Sign Painter | Missouri |
| 35 | Genevieve Backer | 15 | Daughter | — | Missouri |
| 36 | Theresa Backer | 21 | Daughter-in-law | Waitress | Missouri |
| 37 | Theresa Marie Backer | 0 | Granddaughter | — | Missouri |
| 38 | John Mahoney THIS PERSON | 65 | Head | Motorman | Ireland |
| 39 | Mary Mahoney | 64 | Wife | — | Missouri |
| 40 | Francis Mahoney | 30 | Son | Elec Welder | Missouri |
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)