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Mary Mcdonnell — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this Mary Mcdonnell across the 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed) — first a spouse (b.~1910), then head of a 4-person household.
Age 30
b. ~1910
Female
Spouse
Born: Irish Free State
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | McDonnell |
| Given Name | Mary |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 30 |
| Marital Status | Married |
| Birthplace | Irish Free State |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Naturalization Status | Naturalized |
| Additional Details | |
| Highest Grade | 8 |
| 1935 Residence | Same place |
| Birthplace (normalized) | irish free state |
| 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.
4 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Mary Mcdonnell | Spouse | — | 30 | ~1910 |
| Mary Mcdonnell | Daughter | — | 5 | ~1935 |
| Martin Mcdonnell | Head | — | 37 | ~1903 |
| Ann Mcdonnell | Daughter | — | 1 | ~1939 |
Census Appearances
1930
Cook, Illinois
Other, age 22
Cook, Illinois · implied b. ~1908 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McDonnell |
| Given Name | Mary A. |
| Relationship to Head | Servant |
| Sex | F |
| Color / Race | White |
| Age | 22 |
| Marital Status | Single |
| Birthplace | Irish Free State |
| Naturalization Status | Naturalized |
| Year of Immigration | 1929 |
| Father's Birthplace | Irish Free State |
| Mother's Birthplace | Irish Free State |
| Occupation | Servant |
| Industry | Private Family |
| Class of Worker | W |
| Can Read/Write | Yes |
| Mother Tongue | English |
| Birthplace (normalized) | irish free state |
1940
Cook-County, Illinois
Spouse, age 30
Cook-County, Illinois · implied b. ~1910 — 4 household members
| Surname | McDonnell |
| Given Name | Mary |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 30 |
| Marital Status | Married |
| Birthplace | Irish Free State |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Naturalization Status | Naturalized |
| Highest Grade | 8 |
| 1935 Residence | Same place |
| Birthplace (normalized) | irish free state |
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 Mcdonnell across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
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This person
Anchor record
Mary Mcdonnell
Spouse · 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-t0627-00957-00869)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Walter E. Barry | 39 | Head | Owner | Illinois |
| 2 | Elizabeth Barry | 39 | Wife | — | Illinois |
| 3 | Elizabeth Ann Barry | 10 | Daughter | — | Illinois |
| 4 | Eugene Barry | 35 | Head | Owner | Illinois |
| 5 | Charles J. Spatz | 39 | Head | Electrician | Illinois |
| 6 | Nora Spatz | 39 | Wife | — | Illinois |
| 7 | Mary Spatz | 10 | Daughter | — | Illinois |
| 8 | Thomas Spatz | 6 | Son | — | Illinois |
| 9 | Richard Spatz | 1 | Son | — | Illinois |
| 10 | James Murphy | 38 | Head | Repair Man | Irish Free State |
| 11 | Nora Murphy | 35 | Wife | — | Irish Free State |
| 12 | Mary Murphy | 4 | Daughter | — | Illinois |
| 13 | Catherine Murphy | 1 | Daughter | — | Illinois |
| 14 | Martin Mcdonnell | 37 | Head | Policeman | Irish Free State |
| 15 | Mary Mcdonnell THIS PERSON | 30 | Wife | — | Irish Free State |
| 16 | Mary Catherine Mcdonnell | 5 | Daughter | — | Illinois |
| 17 | Ann Elizabeth Mcdonnell | 1 | Daughter | — | Illinois |
| 18 | Henry Schwentker | 41 | Head | Clerk | Illinois |
| 19 | Anna Schwentker | 40 | Wife | — | Iowa |
| 20 | Rita Schwentker | 14 | Daughter | — | Illinois |
| 21 | Doris Schwentker | 8 | Daughter | — | Illinois |
| 22 | Raymond Schwentker | 5 | Son | — | Illinois |
| 23 | James Kavanaugh | 41 | Head | Policeman | Irish Free State |
| 24 | Delia Kavanaugh | 35 | Wife | — | Irish Free State |
| 25 | Thomas Kavanaugh | 5 | Son | — | Illinois |
| 26 | Mary Kavanaugh | 2 | Daughter | — | Illinois |
| 27 | A. M. Purcell | 50 | Head | Letter Carrier | Illinois |
| 28 | Jane Purcell | 41 | Wife | — | Illinois |
| 29 | Jane Purcell | 10 | Daughter | — | Illinois |
| 30 | Mary Purcell | 5 | Daughter | — | Illinois |
| 31 | John Mcdermott | 46 | Head | Policeman | Illinois |
| 32 | Mary Mcdermott | 46 | Wife | — | Illinois |
| 33 | John Mcdermott | 11 | Son | — | Illinois |
| 34 | Robert Mcdermott | 11 | Son | — | Illinois |
| 35 | Oscar Beyer | 65 | Head | — | Germany |
| 36 | Martha Beyer | 61 | Wife | — | Germany |
| 37 | Koepel, Helmuth Beyer | 44 | Nephew | Dairyman | Germany |
| 38 | William L. Campbell | 40 | Head | Publisher | Indiana |
| 39 | Anna Campbell | 50 | Wife | Social Worker | Missouri |
| 40 | Barbara Campbell | 18 | Daughter | New Worker | Huntington |
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)