MH
Mary Hayes — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this Mary Hayes across the 1920, 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed) — first a head (b.~1874), then head of a 4-person household.
Age 66
b. ~1874
Female
Head
Born: Ireland
Widowed
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | Hayes |
| Given Name | Mary |
| Relationship to Head | Head |
| Sex | F |
| Color / Race | White |
| Age | 66 |
| Marital Status | Widowed |
| Birthplace | Ireland |
| 1935 Residence (City) | Chicago City |
| Naturalization Status | Naturalized |
| Additional Details | |
| Highest Grade | No 5 |
| 1935 Residence | Same Place |
| Birth Country | Ireland |
| Birthplace (normalized) | ireland |
| Township / Ward | Chicago City |
| Est. Birth Year | ~1874 |
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 Mary | Age | Birth yr |
|---|---|---|---|---|
| Mary Hayes | Daughter | — | 32 | ~1908 |
| Mary Hayes | Head | — | 66 | ~1874 |
| William Hayes | Son | — | 29 | ~1911 |
| John Hayes | Son | — | 30 | ~1910 |
Census Appearances
1920
Cook, Illinois
Spouse, age 41
Cook, Illinois · implied b. ~1879 — 9 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Hayes |
| Given Name | Mary |
| Relationship to Head | wife |
| Sex | F |
| Color / Race | White |
| Age | 41 |
| Marital Status | Married |
| Birthplace | Ireland |
| Year of Immigration | 1902 |
| Naturalization Status | Naturalized |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Occupation | none |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Mother Tongue | English |
| Birth Country | Ireland |
| Year of Naturalization | 1905 |
| Birthplace (normalized) | ireland |
1930
Cook, Illinois
Spouse, age 53
Cook, Illinois · implied b. ~1877 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Hayes |
| Given Name | Mary |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 53 |
| Marital Status | Married |
| Birthplace | Ireland |
| Naturalization Status | Naturalized |
| Year of Immigration | 1901 |
| Age at First Marriage | 37 |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Can Read/Write | Yes |
| Mother Tongue | English |
| Birth Country | Ireland |
| Birthplace (normalized) | ireland |
1940
Cook-County, Illinois
Head, age 66
Cook-County, Illinois · implied b. ~1874 — 4 household members
| Surname | Hayes |
| Given Name | Mary |
| Relationship to Head | Head |
| Sex | F |
| Color / Race | White |
| Age | 66 |
| Marital Status | Widowed |
| Birthplace | Ireland |
| 1935 Residence (City) | Chicago City |
| Naturalization Status | Naturalized |
| Highest Grade | No 5 |
| 1935 Residence | Same Place |
| Birth Country | Ireland |
| Birthplace (normalized) | ireland |
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 Hayes across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage.
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This person
Anchor record
Mary Hayes
Head · 1940 · age 66 · b. ~1874 · 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-t0627-00944-00576)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Catherine Williams | 5 | Daughter | — | Illinois |
| 2 | John Williams | 3 | Son | — | Illinois |
| 3 | Howard G. Bell | 25 | Head | Clerk | Kansas |
| 4 | Netzly Bell | 53 | Boarder | Inspector | Ohio |
| 5 | William Cahill | 58 | Head | Policeman | Illinois |
| 6 | Julia Cahill | 64 | Wife | — | Illinois |
| 7 | Joseph Vajnerich | 32 | Head | Labor | Scotland |
| 8 | Stephanie Vajnerich | 28 | Wife | — | Illinois |
| 9 | Catherine Vajnerich | 4 | Daughter | — | Illinois |
| 10 | Diane Vajnerich | 1 | Daughter | — | Illinois |
| 11 | Charles Paulanskas | 59 | Head | Labor | Lithuania |
| 12 | Anna Paulanskas | 54 | Wife | — | Lithuania |
| 13 | Margaret Karis | 35 | Daughter | Housewife | England |
| 14 | Lorraine Karis | 12 | Granddaughter | — | Illinois |
| 15 | Susan Williams | 72 | Head | — | Illinois |
| 16 | Eva M. Williams | 46 | Daughter | — | Illinois |
| 17 | Mary Hayes THIS PERSON | 66 | Head | — | Ireland |
| 18 | Mary Hayes | 32 | Daughter | Seamstress | Illinois |
| 19 | John Hayes | 30 | Son | Clerk | Illinois |
| 20 | William Hayes | 29 | Son | Clerk | Illinois |
| 21 | Stanley Baltmeris | 52 | Head | — | Lithuania |
| 22 | Roselyn Baltmeris | 50 | Wife | — | Lithuania |
| 23 | Anthony Baltmeris | 26 | Son | Tireman | Illinois |
| 24 | Joseph Baltmeris | 23 | Son | Labor | Illinois |
| 25 | Anthony Becharnis | 46 | Head | Driver | Lithuania |
| 26 | Emily Becharnis | 47 | Wife | — | Lithuania |
| 27 | Ruth Becharnis | 16 | Daughter | — | Illinois |
| 28 | Anthony Dabray | 55 | Boarder | Labor | Lithuania |
| 29 | Violet Stankus | 58 | Head | — | Lithuania |
| 30 | Anthony Wasilevskas | 52 | Boarder | Loader | Lithuania |
| 31 | Michael Zickus | 33 | Head | Welder | Illinois |
| 32 | Sophie Zickus | 24 | Wife | — | Missouri |
| 33 | Dorothy Zickus | 7 | Daughter | — | Illinois |
| 34 | Anna Bernis | 59 | Head | — | Lithuania |
| 35 | George Belakis | 45 | Boarder | Labor | Lithuania |
| 36 | John Mikolitis | 30 | Head | Packer | Illinois |
| 37 | Anna Mikolitis | 27 | Wife | — | Georgia |
| 38 | Audrey Mikolitis | 8 | Daughter | — | Illinois |
| 39 | John Mikolitis | 7 | Son | — | Illinois |
| 40 | John Lenkus | 42 | Head | Labor | Lithuania |
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)