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Mary Willis — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this Mary Willis across the 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed) — first a spouse (b.~1901), then head of a 12-person household.
Age 39
b. ~1901
Female
Spouse
Born: Virginia
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | Willis |
| Given Name | Mary |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | Black |
| Age | 39 |
| Marital Status | Married |
| Birthplace | Virginia |
| 1935 Residence (City) | Chicago |
| 1935 Residence (County) | Cook |
| Additional Details | |
| Income (1939) | 0 |
| Highest Grade | No 6 |
| 1935 Residence | Same Place |
| Birth State | Virginia |
| Birth Country | United States |
| Birthplace (normalized) | virginia |
| Township / Ward | Chicago |
| Est. Birth Year | ~1901 |
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.
12 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Helen Willis | Daughter | — | 3 | ~1937 |
| Lottie Willis | Daughter | — | 15 | ~1925 |
| Nannie Willis | Daughter | — | 14 | ~1926 |
| Delois Willis | Daughter | — | 9 | ~1931 |
| Louise Willis | Daughter | — | 11 | ~1929 |
| Margaret Willis | Daughter | — | 12 | ~1928 |
| Leslie Willis | Head | — | 47 | ~1893 |
| Edgar Willis | Son | — | ~1940 | |
| Harold Willis | Son | — | 10 | ~1930 |
| Floyd Willis | Son | — | 5 | ~1935 |
| Leslie Willis | Son | — | 17 | ~1923 |
| Mary Willis | Spouse | — | 39 | ~1901 |
Census Appearances
1930
Cook, Illinois
Spouse, age 28
Cook, Illinois · implied b. ~1902 — 8 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Willis |
| Given Name | Mary |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | Black |
| Age | 28 |
| Marital Status | Married |
| Birthplace | Virginia |
| Age at First Marriage | 19 |
| Father's Birthplace | Virginia |
| Mother's Birthplace | Virginia |
| Occupation | none |
| Can Read/Write | Yes |
| Birth State | Virginia |
| Birth Country | United States |
| Birthplace (normalized) | virginia |
1940
Cook-County, Illinois
Spouse, age 39
Cook-County, Illinois · implied b. ~1901 — 12 household members
| Surname | Willis |
| Given Name | Mary |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | Black |
| Age | 39 |
| Marital Status | Married |
| Birthplace | Virginia |
| 1935 Residence (City) | Chicago |
| 1935 Residence (County) | Cook |
| Income (1939) | 0 |
| Highest Grade | No 6 |
| 1935 Residence | Same Place |
| Birth State | Virginia |
| Birth Country | United States |
| Birthplace (normalized) | virginia |
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 Mary Willis across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Willis
Spouse · 1940 · age 39 · b. ~1901 · 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-t0627-00924-00457)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Dallie Walker | 85 | Mother | — | Ohio |
| 42 | George Menary | 66 | Head | Janitor | Indiana |
| 43 | Dollie Menary | 46 | Wife | — | Illinois |
| 44 | Jessie Rivers | 19 | Son | — | Illinois |
| 45 | Joseph Rivers | 17 | Son | New Worker | Illinois |
| 46 | Gloria Lyle | 16 | Niece | — | Illinois |
| 47 | Yates Lyle | 48 | Brother-in-law | Bartender | Illinois |
| 48 | George Wood | 30 | Head | Porter | Indiana |
| 49 | Vera Wood | 26 | Wife | — | Louisiana |
| 50 | George Jr. Wood | 1 | Son | — | Illinois |
| 51 | Leslie Willis | 47 | Head | Cook | Virginia |
| 52 | Mary Willis THIS PERSON | 39 | Wife | — | Virginia |
| 53 | Leslie Jr. Willis | 17 | Son | — | Illinois |
| 54 | Lottie Mae Willis | 15 | Daughter | — | Illinois |
| 55 | Nannie Lee Willis | 14 | Daughter | — | Illinois |
| 56 | Margaret Willis | 12 | Daughter | — | Illinois |
| 57 | Louise Willis | 11 | Daughter | — | Illinois |
| 58 | Harold Willis | 10 | Son | — | Illinois |
| 59 | Delois Willis | 9 | Daughter | — | Illinois |
| 60 | Floyd Willis | 5 | Son | — | Illinois |
| 61 | Helen Willis | 3 | Daughter | — | Illinois |
| 62 | Edgar Willis | 0 | Son | — | Illinois |
| 63 | William Pollard | 48 | Head | Barber | Florida |
| 64 | Anna Pollard | 43 | Wife | Servant | Arkansas |
| 65 | Robert Wheeler | 26 | Son | Porter | Arkansas |
| 66 | Stokes Edgerton | 56 | Head | Laborer | Mississippi |
| 67 | Elizabeth Edgerton | 52 | Wife | — | Illinois |
| 68 | James Wilkins | 37 | Head | Porter | Mississippi |
| 69 | Andrew Lusk | 36 | Head | Porter | Mississippi |
| 70 | Charles Saltpaw | 57 | Head | Janitor | Michigan |
| 71 | Mary Saltpaw | 56 | Wife | — | Tennessee |
| 72 | Charles Jr. Saltpaw | 26 | Son | Auto Mechanic | Illinois |
| 73 | Nathan Branch | 13 | Lodger | — | Illinois |
| 74 | Fred Branch | 12 | Lodger | — | Illinois |
| 75 | Emma Hamilton | 32 | Head | Maid | Tennessee |
| 76 | Mary Hamilton | 12 | Daughter | — | Illinois |
| 77 | Curtis Hamilton | 18 | Daughter | — | Tennessee |
| 78 | Alberta Primm | 40 | Head | Cook | Tennessee |
| 79 | Wallace Locket | 19 | Son | Cook | Illinois |
| 80 | William Mosley | 40 | Head | Laborer | Kentucky |
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)