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Joseph Kowalski — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this Joseph Kowalski across the 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed) — first a son (b.~1928), then head of a 8-person household.
Age 12
b. ~1928
Male
Son
Born: Illinois
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | Kowalski |
| Given Name | Joseph |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 12 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Additional Details | |
| Highest Grade | 5 |
| 1935 Residence | Same place |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Township / Ward | Chicago City |
| Est. Birth Year | ~1928 |
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.
8 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Joseph | Age | Birth yr |
|---|---|---|---|---|
| Joseph Kowalski | Son | — | 12 | ~1928 |
| Edwin Kowalski | Son | — | 9 | ~1931 |
| Bernice Kowalski | Spouse | — | 45 | ~1895 |
| Delores Kowalski | Daughter | — | 15 | ~1925 |
| Pearl Kowalski | Son | — | 20 | ~1920 |
| Henry Kowalski | Son | — | 21 | ~1919 |
| John Kowalski | Head | — | 47 | ~1893 |
| John Kowalski | Son | — | 12 | ~1928 |
Census Appearances
1930
Cook, Illinois
Son, age 1
Cook, Illinois · implied b. ~1929 — 3 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | KOWALSKI |
| Given Name | JOSEPH |
| Relationship to Head | SON |
| Sex | M |
| Color / Race | White |
| Age | 1 |
| Marital Status | Single |
| Birthplace | ILLINOIS |
| Father's Birthplace | POLAND |
| Mother's Birthplace | POLAND |
| Occupation | NONE |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Cook-County, Illinois
Son, age 12
Cook-County, Illinois · implied b. ~1928 — 8 household members
| Surname | Kowalski |
| Given Name | Joseph |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 12 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Highest Grade | 5 |
| 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 Joseph Kowalski across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Joseph Kowalski
Son · 1940 · age 12 · b. ~1928 · Illinois
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Sibling
Henry Kowalski
Sibling · 1940 · age 21
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Edwin Kowalski
Sibling · 1940 · age 9
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Delores Kowalski
Sibling · 1940 · age 15
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
John Kowalski
Sibling · 1940 · age 12
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Pearl 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 — 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-t0627-00987-00585)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Elmer Orange | 26 | Head | Freight Handler | Illinois |
| 2 | Kathryn Orange | 23 | Wife | — | Illinois |
| 3 | Charles Orange | 2 | Son | — | Illinois |
| 4 | John Orange | 1 | Son | — | Illinois |
| 5 | Genevieve Dvorak | 21 | Sister-in-law | — | Illinois |
| 6 | Raymond Nenhecko | 24 | Head | Telephone Operator | Illinois |
| 7 | Mary Nenhecko | 25 | Wife | Janitor | Illinois |
| 8 | Carol Nenhecko | 5 | Daughter | — | Illinois |
| 9 | Patricia Nenhecko | 1 | Daughter | — | Illinois |
| 10 | Walter Gaul | 30 | Head | Grinder | Illinois |
| 11 | Matilda Gaul | 28 | Wife | — | Illinois |
| 12 | Joan Gaul | 7 | Daughter | — | Illinois |
| 13 | Walter Kazlowski | 34 | Head | Clerker | Illinois |
| 14 | Sharon Kazlowski | 25 | Wife | Solder | Illinois |
| 15 | Walter Jr Kazlowski | 2 | Son | — | Illinois |
| 16 | Leo Tomaszynski | 62 | Head | — | Poland |
| 17 | Delia Ellis | 33 | Partner | Laborer | Texas |
| 18 | Le Frank Hunter | 35 | Head | Salesman | Utah |
| 19 | Evelyn Hunter | 29 | Wife | Color Clerk | Illinois |
| 20 | Joseph Pudowski | 55 | Head | Dole Cutter | Michigan |
| 21 | Martha Pudowski | 51 | Wife | — | Illinois |
| 22 | Leonard Pudowski | 25 | Son | Bench-Hand | Illinois |
| 23 | Joseph Parek | 46 | Head | Saw-Filer | Poland |
| 24 | Nellie Parek | 37 | Wife | — | Illinois |
| 25 | Stanley Szerepkowski | 24 | Son-in-law | Cabinet Maker | Illinois |
| 26 | Loretta Szerepkowski | 21 | Daughter | — | Illinois |
| 27 | Stanley Piotrowski | 41 | Head | Packer | Illinois |
| 28 | Bessie Piotrowski | 85 | Mother | — | Illinois |
| 29 | John Kowalski | 47 | Head | Machinist | Brazil |
| 30 | Bernice Kowalski | 45 | Wife | — | Illinois |
| 31 | Henry Kowalski | 21 | Son | Color-Man | Illinois |
| 32 | Pearl Kowalski | 20 | Son | Finisher | Illinois |
| 33 | Delores Kowalski | 15 | Daughter | — | Illinois |
| 34 | John Jr Kowalski | 12 | Son | — | Illinois |
| 35 | Joseph Kowalski THIS PERSON | 12 | Son | — | Illinois |
| 36 | Edwin Kowalski | 9 | Son | — | Illinois |
| 37 | Steve Kamilowski | 50 | Head | Woodworker | Poland |
| 38 | Catherine Kamilowski | 51 | Wife | — | Poland |
| 39 | Walter Kamilowski | 8 | Son | — | Illinois |
| 40 | Matthew Kozlowski | 28 | Son | Feeder | Poland |
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)