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William Leonard — 1940 US Census Record
Model Tree available1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this William Leonard across the 1920, 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed), with identified parents William & William — first a head (b.~1910), then head of a 3-person household.
Age 30
b. ~1910
Male
Head
Born: Illinois
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | Leonard |
| Given Name | William |
| Relationship to Head | head |
| Sex | M |
| Color / Race | White |
| Age | 30 |
| Marital Status | Married |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Additional Details | |
| Occupation | assembler |
| Industry | electrical appliance manuf |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 832 |
| Highest Grade | No 8 |
| 1935 Residence | Same place |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Occupation | Assembler |
| Township / Ward | Chicago City |
| Est. Birth Year | ~1910 |
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 William | Age | Birth yr |
|---|---|---|---|---|
| Patricia Leonard | Daughter | — | 4 | ~1936 |
| William Leonard | Head | — | 30 | ~1910 |
| Lottie Leonard | Spouse | — | 30 | ~1910 |
Census Appearances
1920
Cook, Illinois
Son, age 10
Cook, Illinois · implied b. ~1910 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Leonard |
| Given Name | William |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 10 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Illinois |
| Mother's Birthplace | Illinois |
| Occupation | none |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1930
Cook, Illinois
Son, age 20
Cook, Illinois · implied b. ~1910 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Leonard |
| Given Name | William |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 20 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Illinois |
| Mother's Birthplace | Illinois |
| Occupation | Apprentice |
| Industry | Machine Shop |
| Class of Worker | W |
| Can Read/Write | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Cook-County, Illinois
Head, age 30
Cook-County, Illinois · implied b. ~1910 — 3 household members
| Surname | Leonard |
| Given Name | William |
| Relationship to Head | head |
| Sex | M |
| Color / Race | White |
| Age | 30 |
| Marital Status | Married |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Occupation | assembler |
| Industry | electrical appliance manuf |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 832 |
| Highest Grade | No 8 |
| 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 William Leonard across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father William Leonard (~0.92 confidence) and father William Leonard (~0.92 confidence) and mother Mary Leonard (~0.92 confidence). The pedigree spans 1 generation with 3 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
William Leonard
b. ~1876
Source father
● Household
· direct · ~0.92
Father
William Leonard
b. ~1880
Source father
● Household
· direct · ~0.92
Mother
Mary Leonard
b. ~1885
Source mother
● Household
· direct · ~0.92
This person
Anchor record
William Leonard
Head · 1940 · age 30 · b. ~1910 · 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-t0627-00986-00121)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Agnes Bochat | 41 | Head | Packer | Illinois |
| 42 | Pearl Bochat | 16 | daughter | Braider | Illinois |
| 43 | Harriet Bochat | 15 | daughter | — | Illinois |
| 44 | Alexander Bochat | 10 | son | — | Illinois |
| 45 | Carl Limberg | 44 | head | Watchman | Germany |
| 46 | Elizabeth Limberg | 44 | wife | — | Germany |
| 47 | Elke K Limberg | 11 | daughter | — | Illinois |
| 48 | William Leonard THIS PERSON | 30 | head | Assembler | Illinois |
| 49 | Lottie Leonard | 30 | wife | — | Illinois |
| 50 | Patricia Leonard | 4 | daughter | — | Illinois |
| 51 | Lena Schimke | 53 | head | Cook Helper | Illinois |
| 52 | Emma Schimke | 20 | daughter | Salesgirl | Illinois |
| 53 | Joseph Chekel | 44 | head | Painter | Austria |
| 54 | Caroline Chekel | 54 | wife | — | Roumania |
| 55 | Alice Chekel | 20 | daughter | Salesgirl | Michigan |
| 56 | Irvin Chekel | 19 | son | New Worker | Michigan |
| 57 | Emil X Kountz | 54 | head | — | Germany |
| 58 | Ida Kountz | 52 | sister | Finisher | Illinois |
| 59 | Archer Stephani | 40 | head | Shipping Room Clerk | Illinois |
| 60 | Ruth Stephani | 35 | wife | — | Illinois |
| 61 | Rita Stephani | 10 | daughter | — | Illinois |
| 62 | Donald Stephani | 6 | son | — | Illinois |
| 63 | Michael Fasolotos | 52 | head | Proprietor | Greece |
| 64 | Margaret Fasolotos | 42 | wife | Seamstress | Poland |
| 65 | Nicolas Fasolotos | 21 | son | Lathe Operator | Illinois |
| 66 | Harry Breytspraak | 63 | head | — | Illinois |
| 67 | Josephine Breytspraak | 61 | wife | — | Illinois |
| 68 | George Helfrich | 53 | head | Order Picker | Indiana |
| 69 | Ruth Helfrich | 45 | sister | — | Illinois |
| 70 | Vera Helfrich | 18 | niece | New Worker | Illinois |
| 71 | Kenneth Martini | 29 | head | Maintenance Man | Missouri |
| 72 | Ruth Martini | 29 | wife | — | Missouri |
| 73 | Celia Behen | 54 | head | — | Illinois |
| 74 | Xaveria Skarda | 24 | son | Handy Man | Illinois |
| 75 | Stella Kasdorf | 38 | head | — | Minnesota |
| 76 | Charlotte Kasdorf | 21 | daughter | Stenographer | Minnesota |
| 77 | Martin Fluger | 42 | lodger | Motorman | Illinois |
| 78 | Helene Tischer | 70 | head | — | Germany |
| 79 | Minnie Ammeson | 48 | head | — | Illinois |
| 80 | Evan Ammeson | 24 | son | Freight Tariff Clerk | Illinois |
Pedigree Summary
William
Gen 1 · 3 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)