JM
John Monahan — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Suffolk-County, Massachusetts
Our Model Tree links this John Monahan across the 1910, 1920, 1930 and 1940 US Censuses in Suffolk-County, Massachusetts (XGBoost, ~Confirmed) — first a head (b.~1866), then head of a 6-person household.
Age 74
b. ~1866
Male
Head
Born: New Jersey
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Suffolk-County, Massachusetts |
| Surname | Monahan |
| Given Name | John J. |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 74 |
| Marital Status | Married |
| Birthplace | New Jersey |
| 1935 Residence (City) | Boston |
| 1935 Residence (County) | Suffolk |
| Additional Details | |
| Occupation | Retired |
| Highest Grade | 8 |
| 1935 Residence | Same house |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
| Occupation | Retired |
| Township / Ward | Boston |
| Est. Birth Year | ~1866 |
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.
6 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| Marguerite Monahan | Daughter | — | 35 | ~1905 |
| John Monahan | Head | — | 74 | ~1866 |
| Catherine Monahan | Spouse | — | 67 | ~1873 |
| Richard Monahan | Son | — | 25 | ~1915 |
| Mary Monahan | Daughter | — | 24 | ~1916 |
| Dorothy Egan | Daughter | — | 19 | ~1921 |
Census Appearances
1910
Suffolk, Massachusetts
Head, age 44
Suffolk, Massachusetts · implied b. ~1866 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Monahan |
| Given Name | Joseph F. |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 44 |
| Marital Status | Married |
| Birthplace | New Jersey |
| Years Married | 16 |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Occupation | Conductor |
| Industry | Steam R. R. |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
1920
Suffolk, Massachusetts
Head, age 54
Suffolk, Massachusetts · implied b. ~1866 — 10 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Monahan |
| Given Name | John F. |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 54 |
| Marital Status | Married |
| Birthplace | New Jersey |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Occupation | Conductor |
| Industry | Steam railroad |
| Class of Worker | W |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Home Owned/Rented | O |
| Home Free/Mortgaged | M |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
1930
Suffolk, Massachusetts
Head, age 65
Suffolk, Massachusetts · implied b. ~1865 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Monahan |
| Given Name | John F |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 65 |
| Marital Status | Married |
| Birthplace | New Jersey |
| Age at First Marriage | 28 |
| Father's Birthplace | Irish Free State |
| Mother's Birthplace | Irish Free State |
| Occupation | Conductor |
| Industry | N.H. & H. R.R. |
| Class of Worker | W |
| Can Read/Write | Yes |
| Home Owned/Rented | O |
| Home Value / Rent | 7000 |
| Radio Set | R |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
1940
Suffolk-County, Massachusetts
Head, age 74
Suffolk-County, Massachusetts · implied b. ~1866 — 6 household members
| Surname | Monahan |
| Given Name | John J. |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 74 |
| Marital Status | Married |
| Birthplace | New Jersey |
| 1935 Residence (City) | Boston |
| 1935 Residence (County) | Suffolk |
| Occupation | Retired |
| Highest Grade | 8 |
| 1935 Residence | Same house |
| Birth State | New Jersey |
| Birth Country | United States |
| Birthplace (normalized) | new jersey |
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 John Monahan across 4 US Census years (1910, 1920, 1930 and 1940) in 2 locations, using XGBoost record linkage.
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This person
Anchor record
John Monahan
Head · 1940 · age 74 · b. ~1866 · Massachusetts
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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 — Suffolk-County, Massachusetts
Open full size
1940 US Federal Census — Suffolk-County, Massachusetts
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01678-00083)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Bernice Chase | 5 | daughter | — | Mass |
| 2 | John J. Monahan THIS PERSON | 74 | Head | Retired | New Jersey |
| 3 | Catherine Monahan | 67 | Wife | — | Mass |
| 4 | Marguerite Monahan | 35 | Daughter | — | Mass |
| 5 | Richard Monahan | 25 | Son | — | Mass |
| 6 | Mary E. Monahan | 24 | Daughter | Salesman | Mass |
| 7 | Dorothy Egan | 19 | Daughter | Secretary | Mass |
| 8 | Joseph Ryan | 58 | Head | New Worker | Mass |
| 9 | Catherine Ryan | 59 | Wife | Receiving Clerk | Mass |
| 10 | Aloysius Ryan | 31 | Son | — | Mass |
| 11 | Veronica Ryan | 27 | Daughter | Sorter | Mass |
| 12 | David Ryan | 25 | Son | Stenographer | Mass |
| 13 | Florence Ryan | 24 | Daughter | Typist | Mass |
| 14 | Henry Ryan | 21 | Son | Typist | Mass |
| 15 | Margaret Ryan | 19 | Daughter | Meter Reader | Mass |
| 16 | Arthur Ryan | 17 | Son | Stenographer | Mass |
| 17 | Ralph Quattrucci | 43 | Head | — | Italy |
| 18 | Louise Quattrucci | 44 | Wife | Fireman | Italy |
| 19 | Mary Quattrucci | 20 | daughter | — | Italy |
| 20 | Lena Quattrucci | 17 | daughter | — | Mass |
| 21 | Louis Quattrucci | 15 | Son | Helper | Mass |
| 22 | Philomena Quattrucci | 13 | daughter | — | Mass |
| 23 | Virginia Quattrucci | 12 | daughter | — | Mass |
| 24 | John Quattrucci | 10 | Son | — | Mass |
| 25 | Ralph Jr. Quattrucci | 5 | Son | — | Mass |
| 26 | Arnold Hamilton | 35 | Head | Baker | Penn |
| 27 | Dorothy Hamilton | 33 | Wife | — | Penn |
| 28 | Arnold Hamilton | 13 | Son | — | Mass |
| 29 | Earl Hamilton | 11 | Son | — | Mass |
| 30 | Virginia Hamilton | 10 | daughter | — | Mass |
| 31 | Geraldine Hamilton | 8 | daughter | — | Mass |
| 32 | Ralph Lewis | 20 | Nephew | Helper | Penn |
| 33 | Anthony De Costa | 41 | Head | Stationary Engineer | Rhode Island |
| 34 | Doris De Costa | 36 | Wife | Operator | England |
| 35 | Hazel De Costa | 14 | daughter | — | Mass |
| 36 | Jeanette Covill | 50 | Head | Saleslady | Rhode Island |
| 37 | Clarence Covill | 27 | Son | Accountant | Mass |
| 38 | Elliot Covill | 24 | Son | Salesman | Mass |
| 39 | Frank Finamore | 34 | Head | Cook | Italy |
| 40 | Lucy Finamore | 28 | Wife | — | Italy |
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)