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John Jensen — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this John Jensen across the 1920, 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed) — first a head (b.~1897), then head of a 4-person household.
Age 43
b. ~1897
Male
Head
Born: Denmark
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | Jensen |
| Given Name | John |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 43 |
| Marital Status | Married |
| Birthplace | Denmark |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Naturalization Status | Naturalized |
| Additional Details | |
| Occupation | Clerk |
| Industry | Office |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 2669 |
| Highest Grade | C 3 |
| 1935 Residence | Same place |
| Birth Country | Denmark |
| Birthplace (normalized) | denmark |
| Occupation | Clerk |
| Township / Ward | Chicago City |
| Est. Birth Year | ~1897 |
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.
4 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| John Jensen | Head | — | 43 | ~1897 |
| Neil Jensen | Son | — | 7 | ~1933 |
| John Jensen | Son | — | 11 | ~1929 |
| Harriet Jensen | Spouse | — | 41 | ~1899 |
Census Appearances
1920
Cook, Illinois
Other, age 21
Cook, Illinois · implied b. ~1899 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Jensen |
| Given Name | John |
| Relationship to Head | Roomer |
| Sex | M |
| Color / Race | White |
| Age | 21 |
| Marital Status | Single |
| Birthplace | Denmark |
| Year of Immigration | 1915 |
| Naturalization Status | First papers filed |
| Father's Birthplace | Denmark |
| Mother's Birthplace | Denmark |
| Occupation | Laborer |
| Industry | Factory |
| Class of Worker | W |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Mother Tongue | Danish |
| Birth Country | Denmark |
| Birthplace (normalized) | denmark |
1930
Cook, Illinois
Other, age 32
Cook, Illinois · implied b. ~1898 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Jensen |
| Given Name | John |
| Relationship to Head | Lodger |
| Sex | M |
| Color / Race | White |
| Age | 32 |
| Marital Status | Single |
| Birthplace | Denmark |
| Naturalization Status | Alien |
| Year of Immigration | 1915 |
| Father's Birthplace | Denmark |
| Mother's Birthplace | Denmark |
| Occupation | Floor layer |
| Industry | General |
| Class of Worker | W |
| Can Read/Write | Yes |
| Mother Tongue | Danish |
| Veteran | No |
| Birth Country | Denmark |
| Birthplace (normalized) | denmark |
1940
Cook-County, Illinois
Head, age 43
Cook-County, Illinois · implied b. ~1897 — 4 household members
| Surname | Jensen |
| Given Name | John |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 43 |
| Marital Status | Married |
| Birthplace | Denmark |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Naturalization Status | Naturalized |
| Occupation | Clerk |
| Industry | Office |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 2669 |
| Highest Grade | C 3 |
| 1935 Residence | Same place |
| Birth Country | Denmark |
| Birthplace (normalized) | denmark |
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 Jensen across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage.
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This person
Anchor record
John Jensen
Head · 1940 · age 43 · b. ~1897 · Illinois
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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-t0627-01000-00005)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | May Johnson | 47 | Wife | — | Iowa |
| 42 | Fred Lang | 30 | Son-in-law | Mechanic | Illinois |
| 43 | Clara Lang | 29 | Daughter | — | Iowa |
| 44 | James Lang | 5 | Son | — | — |
| 45 | Charles Magnuson | 17 | Lodger | — | Illinois |
| 46 | Robert Clark | 29 | Head | Own Business | Illinois |
| 47 | Evelyn Clark | 25 | Wife | — | Iowa |
| 48 | Charles Clark | 6 | Son | — | — |
| 49 | Patricia Clark | 5 | Daughter | — | — |
| 50 | Carmela Raruso | 72 | Head | — | — |
| 51 | Phillip Raruso | 44 | Son | Salesman | Illinois |
| 52 | Josephine Raruso | 38 | Daughter | Operator | Illinois |
| 53 | John Jensen THIS PERSON | 43 | Head | Clerk | Denmark |
| 54 | Harriet Jensen | 41 | Wife | — | Illinois |
| 55 | John Jr. Jensen | 11 | Son | — | Illinois |
| 56 | Neil Jensen | 7 | Son | — | Illinois |
| 57 | Alex Kueffler | 41 | Head | Agent | Illinois |
| 58 | Margaret Kueffler | 38 | Wife | — | Iowa |
| 59 | Alvera Kueffler | 3 | Daughter | — | — |
| 60 | Charles A. Bishop | 74 | Head | Own Business | Illinois |
| 61 | Anna Bishop | 70 | Wife | — | Michigan |
| 62 | George A. Jennison | 57 | Head | Chauffeur | Illinois |
| 63 | Harriet Jennison | 55 | Wife | — | Norway |
| 64 | Kenneth Jennison | 25 | Son | Laborer | Illinois |
| 65 | Dorothy Jennison | 15 | Daughter | — | Illinois |
| 66 | Olaf Olson | 49 | Head | Own Business | Illinois |
| 67 | Hilmer Olson | 46 | Brother | Own Business | Illinois |
| 68 | Emma Mae Olson | 37 | Sister | Teacher | Illinois |
| 69 | William Peace | 47 | Head | Sales Manager | Kansas |
| 70 | Ruth Peace | 42 | Wife | — | Illinois |
| 71 | William Jr. Peace | 20 | Son | — | Illinois |
| 72 | Marie Peace | 15 | Daughter | — | Illinois |
| 73 | Charles Peace | 13 | Son | — | Illinois |
| 74 | Joyce Peace | 8 | Daughter | — | Illinois |
| 75 | Eunice Peace | 6 | Daughter | — | — |
| 76 | Barbara Peace | 3 | Daughter | — | — |
| 77 | Edward J. Barron | 54 | Head | — | Illinois |
| 78 | Delia Barron | 50 | Wife | — | Illinois |
| 79 | Catharine Barron | 26 | Daughter | Stenographer | Illinois |
| 80 | Robert Barron | 21 | Son | Mechanic | Illinois |
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)