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John Kowalski — 1940 US Census Record
Linked across censuses1940 United States Federal Census · St.-Joseph-County, Indiana
Our Model Tree links this John Kowalski across the 1930 and 1940 US Censuses in St.-Joseph-County, Indiana (XGBoost, ~Confirmed) — first a son (b.~1915), then head of a 9-person household.
Age 25
b. ~1915
Male
Son
Born: Indiana
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | St.-Joseph-County, Indiana |
| Surname | Kowalski |
| Given Name | John |
| Relationship to Head | son |
| Sex | M |
| Color / Race | White |
| Age | 25 |
| Marital Status | Single |
| Birthplace | Indiana |
| 1935 Residence (City) | South Bend |
| 1935 Residence (County) | St. Joseph |
| Additional Details | |
| Occupation | laborer |
| Industry | Toy Mfg. |
| Class of Worker | PW |
| Hours Worked | 0 |
| Income (1939) | 988 |
| Highest Grade | No 7 |
| 1935 Residence | Same place |
| Birth State | Indiana |
| Birth Country | United States |
| Birthplace (normalized) | indiana |
| Occupation | Laborer |
| Township / Ward | South Bend |
| Est. Birth Year | ~1915 |
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.
9 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| Frank Kowalski | Son | — | 20 | ~1920 |
| Bernard Kowalski | Son | — | 12 | ~1928 |
| Mary Kowalski | Daughter | — | 14 | ~1926 |
| Harry Kowalski | Son | — | 18 | ~1922 |
| Dorothy Kowalski | Daughter | — | 16 | ~1924 |
| Ervin Kowalski | Son | — | 23 | ~1917 |
| John Kowalski | Son | — | 25 | ~1915 |
| Anna Kowalski | Head | — | 47 | ~1893 |
| Stanley Kowalski | Son | — | 28 | ~1912 |
Census Appearances
1930
St Joseph, …
Son, age 14
St Joseph, Indiana · implied b. ~1916 — 10 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Kowalski |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 14 |
| Marital Status | Single |
| Birthplace | Indiana |
| Father's Birthplace | Poland |
| Mother's Birthplace | Poland |
| Can Read/Write | Yes |
| Birth State | Indiana |
| Birth Country | United States |
| Birthplace (normalized) | indiana |
1940
St.-Joseph-County, Indiana
Son, age 25
St.-Joseph-County, Indiana · implied b. ~1915 — 9 household members
| Surname | Kowalski |
| Given Name | John |
| Relationship to Head | son |
| Sex | M |
| Color / Race | White |
| Age | 25 |
| Marital Status | Single |
| Birthplace | Indiana |
| 1935 Residence (City) | South Bend |
| 1935 Residence (County) | St. Joseph |
| Occupation | laborer |
| Industry | Toy Mfg. |
| Class of Worker | PW |
| Hours Worked | 0 |
| Income (1939) | 988 |
| Highest Grade | No 7 |
| 1935 Residence | Same place |
| Birth State | Indiana |
| Birth Country | United States |
| Birthplace (normalized) | indiana |
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 Kowalski across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
John Kowalski
Son · 1940 · age 25 · b. ~1915 · Indiana
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Sibling
Harry Kowalski
Sibling · 1940 · age 18
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Stanley Kowalski
Sibling · 1940 · age 28
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Bernard Kowalski
Sibling · 1940 · age 12
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Ervin Kowalski
Sibling · 1940 · age 23
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Dorothy Kowalski
Sibling · 1940 · age 16
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Mary Kowalski
Sibling · 1940 · age 14
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Frank Kowalski
Sibling · 1940 · age 20
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 — St.-Joseph-County, Indiana
Open full size
1940 US Federal Census — St.-Joseph-County, Indiana
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01135-00582)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Corrine Bonney | 42 | wife | — | Oklahoma |
| 42 | William Bonney | 8 | son | — | Michigan |
| 43 | Morton A. Martin | 46 | Head | Barber | Arkansas |
| 44 | Max Melend | 59 | Lodger | Laborer | Mississippi |
| 45 | James Asher | 50 | Lodger | Laborer | Mississippi |
| 46 | Wander Victor | 50 | Lodger | Laborer | Michigan |
| 47 | Elizabeth Nemeth | 55 | Head | Operator | Hungary |
| 48 | Louis Nemeth | 25 | son | Investigator | Indiana |
| 49 | Valentine Delinski | 59 | Head | Policeman | Indiana |
| 50 | Laura Delinski | 54 | wife | — | Indiana |
| 51 | Mary A. Delinski | 20 | daughter | Coremaker | Indiana |
| 52 | Valentine Jr. Delinski | 15 | son | — | Indiana |
| 53 | Thomas Zytowski | 63 | Father in law | — | Poland |
| 54 | Anna Kowalski | 47 | Head | Homework | Poland |
| 55 | Stanley Kowalski | 28 | son | Laborer | Indiana |
| 56 | John Kowalski THIS PERSON | 25 | son | Laborer | Indiana |
| 57 | Ervin Kowalski | 23 | son | Laborer | Indiana |
| 58 | Frank Kowalski | 20 | son | New Worker | Indiana |
| 59 | Harry Kowalski | 18 | son | — | Indiana |
| 60 | Dorothy Kowalski | 16 | daughter | — | Indiana |
| 61 | Mary Kowalski | 14 | daughter | — | Indiana |
| 62 | Bernard Kowalski | 12 | son | — | Indiana |
| 63 | Genevieve Novak | 29 | Head | Laborer | Indiana |
| 64 | Valentine Novak | 31 | brother | Truck Driver | Indiana |
| 65 | Andrew Novak | 25 | brother | Watchman | Indiana |
| 66 | Dorothy Twistowy | 16 | niece | — | Indiana |
| 67 | Margaret Twistowy | 14 | niece | — | Indiana |
| 68 | Valentine Jurgonski | 35 | Head | Laborer | Indiana |
| 69 | Marie Jurgonski | 34 | wife | Laborer | Indiana |
| 70 | Eugene Jurgonski | 10 | son | — | Indiana |
| 71 | Evelyn Jurgonski | 9 | daughter | — | Indiana |
| 72 | Leonard Jurgonski | 6 | son | — | Indiana |
| 73 | Frank Bugalski | 51 | Head | Laborer | Indiana |
| 74 | Verna Bugalski | 53 | wife | Laborer | Indiana |
| 75 | Dorothy Bugalski | 21 | daughter | Laborer | Indiana |
| 76 | Mary Kolesiak | 60 | Head | — | Poland |
| 77 | Honorata Kolesiak | 26 | daughter | Clerk | Indiana |
| 78 | Raymond Kolesiak | 25 | son | Laborer | Indiana |
| 79 | Alfreda Kolesiak | 27 | daughter in law | Laborer | Indiana |
| 80 | Ignacius Kazmierczyk | 39 | Head | Laborer | Indiana |
Related Census Records
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)