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Mary Mcgrath — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this Mary Mcgrath across the 1920, 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed) — first a head (b.~1886), then head of a 7-person household.
Age 54
b. ~1886
Female
Head
Born: Ireland
Widowed
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | McGrath |
| Given Name | Mary |
| Relationship to Head | Head |
| Sex | F |
| Color / Race | White |
| Age | 54 |
| Marital Status | Widowed |
| Birthplace | Ireland |
| 1935 Residence (City) | Chicago |
| 1935 Residence (County) | Cook |
| Naturalization Status | Naturalized |
| Additional Details | |
| Occupation | Clerk |
| Industry | City Court |
| Class of Worker | GW |
| Hours Worked | 40 |
| Income (1939) | 2000 |
| Highest Grade | No 8 |
| 1935 Residence | Same house |
| Birth Country | Ireland |
| Birthplace (normalized) | ireland |
| Occupation | Clerk |
| Township / Ward | Chicago |
| Est. Birth Year | ~1886 |
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.
7 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Josephine Mcgrath | Daughter | — | 24 | ~1916 |
| Mary Mcgrath | Daughter | — | 16 | ~1924 |
| Mary Mcgrath | Head | — | 54 | ~1886 |
| John Mcgrath | Son | — | 21 | ~1919 |
| Frank Mcgrath | Son | — | 22 | ~1918 |
| Thomas Mcgrath | Son | — | 13 | ~1927 |
| James Mcgrath | Son | — | 27 | ~1913 |
Census Appearances
1920
Cook, Illinois
Spouse, age 30
Cook, Illinois · implied b. ~1890 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McGrath |
| Given Name | Mary |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 30 |
| Marital Status | Married |
| Birthplace | Ireland |
| Year of Immigration | 1907 |
| Naturalization Status | First papers filed |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Mother Tongue | English |
| Birth Country | Ireland |
| Birthplace (normalized) | ireland |
1930
Cook, Illinois
Spouse, age 41
Cook, Illinois · implied b. ~1889 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McGrath |
| Given Name | Mary |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 41 |
| Marital Status | Married |
| Birthplace | Ireland |
| Naturalization Status | Naturalized |
| Year of Immigration | 1907 |
| Age at First Marriage | 26 |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Occupation | Waitress |
| Industry | Tea Room |
| Class of Worker | W |
| Can Read/Write | Yes |
| Mother Tongue | Irish |
| Birth Country | Ireland |
| Birthplace (normalized) | ireland |
1940
Cook-County, Illinois
Head, age 54
Cook-County, Illinois · implied b. ~1886 — 7 household members
| Surname | McGrath |
| Given Name | Mary |
| Relationship to Head | Head |
| Sex | F |
| Color / Race | White |
| Age | 54 |
| Marital Status | Widowed |
| Birthplace | Ireland |
| 1935 Residence (City) | Chicago |
| 1935 Residence (County) | Cook |
| Naturalization Status | Naturalized |
| Occupation | Clerk |
| Industry | City Court |
| Class of Worker | GW |
| Hours Worked | 40 |
| Income (1939) | 2000 |
| Highest Grade | No 8 |
| 1935 Residence | Same house |
| 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 Mcgrath 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 Mcgrath
Head · 1940 · age 54 · b. ~1886 · 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-t0627-00949-00866)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | William H Williams | 36 | Head | Chauffeur | Illinois |
| 42 | Rose Williams | 35 | Wife | Graph Oper | Illinois |
| 43 | Robert Williams | 18 | Son | Chauffeur | Illinois |
| 44 | Walter W Think | 70 | Head | — | Connecticut |
| 45 | Lydia Think | 46 | Daughter | — | Illinois |
| 46 | Mary Mcgrath THIS PERSON | 54 | Head | Clerk | Ireland |
| 47 | James Mcgrath | 27 | Son | Deputy | Illinois |
| 48 | Josephine Mcgrath | 24 | Daughter | Teacher | Illinois |
| 49 | Frank Mcgrath | 22 | Son | Clerk | Illinois |
| 50 | John Mcgrath | 21 | Son | — | Illinois |
| 51 | Mary Alice Mcgrath | 16 | Daughter | — | Illinois |
| 52 | Thomas Mcgrath | 13 | Son | — | Illinois |
| 53 | Mary Farrell | 71 | Head | — | Ireland |
| 54 | Frank Berger | 46 | Boarder | Labor | Illinois |
| 55 | Thomas Berger | 8 | Boarder son | — | Illinois |
| 56 | Frank Jr Berger | 4 | Boarder son | — | Illinois |
| 57 | Vincent Olson | 27 | Head | Superintendent | Illinois |
| 58 | Marie Olson | 25 | Wife | — | Illinois |
| 59 | Vincent Jr Olson | 1 | Son | — | Illinois |
| 60 | Frances Olson | 0 | Son | — | Illinois |
| 61 | James Neary | 35 | Head | Stock Handler | Illinois |
| 62 | Ella Neary | 31 | Wife | — | Illinois |
| 63 | James Neary | 12 | Son | — | Illinois |
| 64 | Mary Neary | 10 | Daughter | — | Illinois |
| 65 | Richard Neary | 5 | Son | — | Illinois |
| 66 | John Burns | 34 | Head | Police | Illinois |
| 67 | Mary Burns | 34 | Wife | — | Illinois |
| 68 | John Burns | 6 | Son | — | Illinois |
| 69 | Elizabeth Burns | 4 | Daughter | — | Illinois |
| 70 | Jacob Wagner | 31 | Head | Janitor | Illinois |
| 71 | Mary Ellen Wagner | 27 | Wife | — | Ireland |
| 72 | Mary Ellen Wagner | 9 | Daughter | — | Illinois |
| 73 | Ida May Wagner | 5 | Daughter | — | Illinois |
| 74 | Bernard Jos Wagner | 0 | Son | — | Illinois |
| 75 | Catherine Burns | 47 | Head | — | Pennsylvania |
| 76 | Peter C Burns | 24 | Son | App. Printer | Illinois |
| 77 | Bernard J Burns | 23 | Son | Book Binder | Illinois |
| 78 | Edward Stager | 63 | Head | Foreman | Wisconsin |
| 79 | Albert Stager | 67 | Brother | — | Wisconsin |
| 80 | Michael Barrett | 44 | Head | Labor | 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)