ON
Oscar Nelson — 1940 US Census Record
Model Tree available1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this Oscar Nelson across the 1910, 1920, 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed), with identified parents Andrew & Theresa — first a head (b.~1897), then head of a 3-person household.
Age 43
b. ~1897
Male
Head
Born: Illinois
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | Nelson |
| Given Name | Oscar J. |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 43 |
| Marital Status | Married |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago |
| 1935 Residence (County) | Cook |
| Additional Details | |
| Occupation | Adjuster |
| Industry | Insurance Company |
| Class of Worker | PW |
| Hours Worked | 50 |
| Income (1939) | 2780 |
| Highest Grade | No 8 |
| 1935 Residence | Same house |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Occupation | Adjuster |
| Township / Ward | Chicago |
| 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.
3 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Oscar | Age | Birth yr |
|---|---|---|---|---|
| Joan Nelson | Daughter | — | 13 | ~1927 |
| Oscar Nelson | Head | — | 43 | ~1897 |
| Agnes Nelson | Spouse | — | 41 | ~1899 |
Census Appearances
1910
Cook, Illinois
Son, age 13
Cook, Illinois · implied b. ~1897 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Nelson |
| Given Name | Oscar A |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 13 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Sweden |
| Mother's Birthplace | Sweden |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1920
Cook, Illinois
Son, age 23
Cook, Illinois · implied b. ~1897 — 10 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Nelson |
| Given Name | Oscar |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 23 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Sweden |
| Mother's Birthplace | Sweden |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1930
Cook, Illinois
Son, age 32
Cook, Illinois · implied b. ~1898 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Nelson |
| Given Name | Oscar |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 32 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Sweden |
| Mother's Birthplace | Sweden |
| Occupation | Clerk |
| Industry | Railroad |
| Class of Worker | W |
| Can Read/Write | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Cook-County, Illinois
Head, age 43
Cook-County, Illinois · implied b. ~1897 — 3 household members
| Surname | Nelson |
| Given Name | Oscar J. |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 43 |
| Marital Status | Married |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago |
| 1935 Residence (County) | Cook |
| Occupation | Adjuster |
| Industry | Insurance Company |
| Class of Worker | PW |
| Hours Worked | 50 |
| Income (1939) | 2780 |
| Highest Grade | No 8 |
| 1935 Residence | Same house |
| 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 Oscar Nelson across 4 US Census years (1910, 1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father Andrew Nelson (~0.92 confidence) and mother Theresa Nelson (~0.92 confidence) and mother Ingeborg Nelson (~0.92 confidence) and father Chas Nelson (~0.92 confidence) and mother Elona Nelson (~0.92 confidence). The pedigree spans 1 generation with 5 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
Andrew Nelson
b. ~1857
Source father
● Household
· direct · ~0.92
Mother
Theresa Nelson
b. ~1857
Source mother
● Household
· direct · ~0.92
Mother
Ingeborg Nelson
b. ~1862
Source mother
● Household
· direct · ~0.92
Father
Chas Nelson
b. ~1866
Source father
● Household
· direct · ~0.92
Mother
Elona Nelson
b. ~1871
Source mother
● Household
· direct · ~0.92
This person
Anchor record
Oscar Nelson
Head · 1940 · age 43 · b. ~1897 · Illinois
★ 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 — 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-t0627-01021-00631)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Michael Franke | 57 | Head | Salesman | Illinois |
| 42 | Emma F. Reed | 57 | Head | — | Illinois |
| 43 | Arthur Reed | 62 | Brother | — | Illinois |
| 44 | Harry B. Baumgardner | 32 | Head | Salesman | Ohio |
| 45 | Ruth Baumgardner | 32 | Wife | — | West Virginia |
| 46 | Richard Baumgardner | 14 | Son | — | Ohio |
| 47 | John D. Erick | 41 | Head | Salesman | Illinois |
| 48 | Bertha C. Erick | 50 | Wife | — | Iowa |
| 49 | Martha D. Lemke | 64 | Head | — | Germany |
| 50 | Irvine J. Graham | 44 | Head | Manager | New York |
| 51 | Elda Graham | 40 | Wife | — | Illinois |
| 52 | Howard Sabin | 27 | Son-in-law | Trimming | Wisconsin |
| 53 | Rose Marie Sabin | 22 | Daughter | Bookkeeper | Illinois |
| 54 | John Hansen | 73 | Head | Agent | Germany |
| 55 | Malie Hansen | 71 | Wife | — | Illinois |
| 56 | Elsie Hansen | 42 | Daughter | — | Illinois |
| 57 | Sime Karpel | 77 | Brother-in-law | — | Illinois |
| 58 | Emma Karpel | 74 | Sister-in-law | — | Illinois |
| 59 | Charles E. Peterson | 60 | Head | Minister | Missouri |
| 60 | Nell Peterson | 56 | Wife | — | Missouri |
| 61 | Oscar J. Nelson THIS PERSON | 43 | Head | Adjuster | Illinois |
| 62 | Agnes Nelson | 41 | Wife | — | Illinois |
| 63 | Joan Nelson | 13 | Daughter | — | Illinois |
| 64 | Joseph Braun | 34 | Head | Chemist | Ohio |
| 65 | Blanche Braun | 35 | Wife | — | Texas |
| 66 | Marilyn Braun | 8 | Daughter | — | Illinois |
| 67 | Elaine Braun | 2 | Daughter | — | Illinois |
| 68 | Edward Clasen | 52 | Head | Bookkeeper | Iowa |
| 69 | Edna Clasen | 46 | Wife | — | Illinois |
| 70 | Lois Clasen | 16 | Daughter | — | Illinois |
| 71 | Lois Mary Clasen | 15 | Daughter | — | Illinois |
| 72 | Margaret Timke | 54 | Head | — | Illinois |
| 73 | Robert Timke | 26 | Son | Clerk | Illinois |
| 74 | Bernard F. Knauer | 45 | Head | Engineer | Illinois |
| 75 | Emma Knauer | 40 | Wife | — | Illinois |
| 76 | Paul Zaring | 37 | Son-in-law | Manager | Indiana |
| 77 | Margaret Zaring | 35 | Daughter | Clerical | Illinois |
| 78 | Nellie W. Bannick | 48 | Head | — | Illinois |
| 79 | Patrick H. Welsch | 71 | Brother | — | Illinois |
| 80 | Helen Jane Welsch | 11 | Grand-niece | — | Illinois |
Pedigree Summary
Oscar
Gen 1 · 5 parents
~0.92
Max depth 4 (1900–1950 window)
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)