JK
John Kozlowski — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Hudson-County, New Jersey
Our Model Tree links this John Kozlowski across the 1930 and 1940 US Censuses in Hudson-County, New Jersey (XGBoost, ~Confirmed) — first a son (b.~1919), then head of a 6-person household.
Age 21
b. ~1919
Male
Son
Born: New Jersey
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Hudson-County, New Jersey |
| Surname | Kozlowski |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 21 |
| Marital Status | Single |
| Birthplace | New Jersey |
| 1935 Residence (City) | Gutenberg |
| 1935 Residence (County) | Hudson |
| Additional Details | |
| Occupation | Truck Driver |
| Industry | Mason's |
| Class of Worker | PW |
| Hours Worked | 48 |
| Income (1939) | 1400 |
| Highest Grade | Hs 2 |
| 1935 Residence | Same place |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
| Occupation | Truck Driver |
| Township / Ward | Gutenberg |
| Est. Birth Year | ~1919 |
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.
6 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| John Kozlowski | Son | — | 21 | ~1919 |
| Frank Kozlowski | Son | — | 18 | ~1922 |
| Stanley Kozlowski | Son | — | 16 | ~1924 |
| Karol Kozlowski | Head | — | 59 | ~1881 |
| Teofila Kozlowski | Spouse | — | 57 | ~1883 |
| Theodore Kozlowski | Son | — | 20 | ~1920 |
Census Appearances
1930
Union, New …
Son, age 10
Union, New Jersey · implied b. ~1920 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Kozlowsky |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 10 |
| Marital Status | Single |
| Birthplace | New Jersey |
| Father's Birthplace | Poland |
| Mother's Birthplace | Poland |
| Can Read/Write | Yes |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
1940
Hudson-County, New …
Son, age 21
Hudson-County, New Jersey · implied b. ~1919 — 6 household members
| Surname | Kozlowski |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 21 |
| Marital Status | Single |
| Birthplace | New Jersey |
| 1935 Residence (City) | Gutenberg |
| 1935 Residence (County) | Hudson |
| Occupation | Truck Driver |
| Industry | Mason's |
| Class of Worker | PW |
| Hours Worked | 48 |
| Income (1939) | 1400 |
| Highest Grade | Hs 2 |
| 1935 Residence | Same place |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
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 Kozlowski across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
John Kozlowski
Son · 1940 · age 21 · b. ~1919 · New Jersey
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Sibling
Theodore Kozlowski
Sibling · 1940 · age 20
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Stanley Kozlowski
Sibling · 1940 · age 16
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Frank Kozlowski
Sibling · 1940 · age 18
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 — Hudson-County, New Jersey
Open full size
1940 US Federal Census — Hudson-County, New Jersey
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-02347-00721)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Paul Young | 53 | Head | Laborer | New Jersey |
| 42 | Anna Young | 52 | Wife | — | New Jersey |
| 43 | John Young | 31 | Son | Laborer | New Jersey |
| 44 | Mildred Young | 29 | Daughter | Office Worker | New Jersey |
| 45 | Anna Young | 27 | Daughter | Office Worker | New Jersey |
| 46 | Paul Jr. Young | 23 | Son | Chauffeur | New Jersey |
| 47 | George W. Monbleau | 35 | Head | Salesman | Ohio |
| 48 | Hazel M. Monbleau | 33 | Wife | — | New Jersey |
| 49 | Elizabeth Vogt | 62 | Head | — | New Jersey |
| 50 | Katherine Vogt | 61 | Sister | — | New Jersey |
| 51 | Helen M. Bischoff | 27 | Niece | Operator | New Jersey |
| 52 | Jacob A. Turatiz | 57 | Head | Washer | Czecho-Slovakia |
| 53 | Tekla Turatiz | 50 | Wife | — | Czecho-Slovakia |
| 54 | Ferdinand Turatiz | 27 | Son | Assembler | New Jersey |
| 55 | Sophie Turatiz | 25 | Daughter | Silk Worker | New Jersey |
| 56 | Michael Hennick | 43 | Head | Laborer | New Jersey |
| 57 | Mary Hennick | 54 | Wife | — | New Jersey |
| 58 | Michael Jr. Hennick | 21 | Son | Gas Station | New Jersey |
| 59 | Jacob Hennick | 16 | Son | — | New Jersey |
| 60 | Karol Kozlowski | 59 | Head | Painter | Poland |
| 61 | Teofila Kozlowski | 57 | Wife | — | Poland |
| 62 | Theodore Kozlowski | 20 | Son | Butcher | New Jersey |
| 63 | John Kozlowski THIS PERSON | 21 | Son | Truck Driver | New Jersey |
| 64 | Frank Kozlowski | 18 | Son | — | New Jersey |
| 65 | Stanley Kozlowski | 16 | Son | Helper | New Jersey |
| 66 | Alphonso Perguidi | 50 | Head | Barber | Italy |
| 67 | Mary Perguidi | 43 | Wife | — | Italy |
| 68 | John M. Lanza | 54 | Head | Collector | New Jersey |
| 69 | Doris F. Lanza | 49 | Wife | — | Germany |
| 70 | Valentine J. Thellmann | 53 | Head | — | New York |
| 71 | Caroline Thellmann | 53 | Wife | — | New Jersey |
| 72 | Gertrude Thellmann | 24 | Daughter | Operator | New Jersey |
| 73 | Lois E. Thellmann | 22 | Daughter | Clerk | New Jersey |
| 74 | John S. Lisen | 54 | Head | Watchman | New Jersey |
| 75 | Mary Lisen | 53 | Wife | — | New Jersey |
| 76 | John J. Lisen | 26 | Son | Barber Shop | New Jersey |
| 77 | Michael Lisen | 22 | Son | Clerk | New Jersey |
| 78 | Daniel Slank | 42 | Head | Carpenter | New Jersey |
| 79 | Marie Slank | 41 | Wife | Bookkeeper | New Jersey |
| 80 | Milan Slank | 13 | Son | — | New Jersey |
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)