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John Mcmahon — 1930 US Census Record
Linked across censuses1930 United States Federal Census · Suffolk, Massachusetts
Our Model Tree links this John Mcmahon across the 1920, 1930 and 1940 US Censuses in Suffolk, Massachusetts (XGBoost, ~Confirmed) — first a head (b.~1869), then head of a 6-person household.
Age 61
b. ~1869
Male
Head
Born: Massachusetts
Married
1930 Census Record Details
| Census Year | 1930 |
| Location | Suffolk, Massachusetts |
| Surname | McMahon |
| Given Name | John H |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 61 |
| Marital Status | Married |
| Birthplace | Massachusetts |
| Age at First Marriage | 36 |
| Father's Birthplace | Irish Free State |
| Mother's Birthplace | Irish Free State |
| Additional Details | |
| Occupation | Sheet Metal Worker |
| Industry | Sheet Metal |
| Class of Worker | W |
| Can Read/Write | Yes |
| Home Owned/Rented | R |
| Home Value / Rent | 40.00 |
| Radio Set | R |
| Veteran | No |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
| Occupation | Sheet Metal Worker |
| Township / Ward | Boston City |
| Est. Birth Year | ~1869 |
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 1930 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| Josephine Mcmahon | Daughter | — | 24 | ~1906 |
| John Mcmahon | Head | — | 61 | ~1869 |
| James Mcmahon | Other | — | 34 | ~1896 |
| Joseph Mcmahon | Other | — | 38 | ~1892 |
| Annie Mcmahon | Other | — | 51 | ~1879 |
| Steven Mcmahon | Other | — | 53 | ~1877 |
Census Appearances
1920
Suffolk, Massachusetts
Head, age 53
Suffolk, Massachusetts · implied b. ~1867 — 3 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McMahon |
| Given Name | John J |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 53 |
| Marital Status | Married |
| Birthplace | Massachusetts |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Massachusetts |
| Occupation | Merchant |
| Industry | Groceries |
| Class of Worker | Em |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Home Owned/Rented | O |
| Home Free/Mortgaged | M |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1930
Suffolk, Massachusetts
Head, age 61
Suffolk, Massachusetts · implied b. ~1869 — 6 household members
| Surname | McMahon |
| Given Name | John H |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 61 |
| Marital Status | Married |
| Birthplace | Massachusetts |
| Age at First Marriage | 36 |
| Father's Birthplace | Irish Free State |
| Mother's Birthplace | Irish Free State |
| Occupation | Sheet Metal Worker |
| Industry | Sheet Metal |
| Class of Worker | W |
| Can Read/Write | Yes |
| Home Owned/Rented | R |
| Home Value / Rent | 40.00 |
| Radio Set | R |
| Veteran | No |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
1940
Suffolk-County, Massachusetts
Other, age 71
Suffolk-County, Massachusetts · implied b. ~1869 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McMahon |
| Given Name | John H. |
| Relationship to Head | FATHER IN LAW |
| Sex | M |
| Color / Race | White |
| Age | 71 |
| Marital Status | Widowed |
| Birthplace | Massachusetts |
| 1935 Residence (City) | Boston City |
| 1935 Residence (County) | Suffolk |
| Occupation | SHEET METAL WKR. |
| Industry | RAILWAY CO. |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 252 |
| Highest Grade | No 8 |
| 1935 Residence | Same place |
| Birth State | Massachusetts |
| Birth Country | United States |
| Birthplace (normalized) | massachusetts |
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 Mcmahon across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage.
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This person
Anchor record
John Mcmahon
Head · 1930 · age 61 · b. ~1869 · Massachusetts
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Confirmed / household (~0.90+)
Probable / derived (~0.65–0.89)
Candidate (<0.65, unverified)
Original Census Page
1930 US Federal Census — Suffolk, Massachusetts
Open full size
1930 US Federal Census — Suffolk, Massachusetts
Page Contents
50 people indexed on this census page (ia:1930:massachusettscensus00reel946:1033)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | John J Mclean | 38 | Head | Driver | Massachusetts |
| 2 | Helen D Mclean | 36 | Wife-H | — | Massachusetts |
| 3 | Helen Mclean | 11 | Daughter | — | Massachusetts |
| 4 | Margaret Mclean | 11 | Daughter | — | Massachusetts |
| 5 | James T Banford | 45 | Head | Carpenter | England |
| 6 | Ada Banford | 45 | Wife-H | — | England |
| 7 | Elizabeth Banford | 19 | Daughter | Filing Clerk | Massachusetts |
| 8 | Oldie Banford | 11 | Daughter | — | Massachusetts |
| 9 | Archibald Macdonald | 50 | Head | State Agent | Scotland |
| 10 | Margaret Macdonald | 43 | Wife-H | — | Scotland |
| 11 | Helen Whiteford | 72 | Aunt | — | Scotland |
| 12 | William Macdonald | 7 | Son | — | Massachusetts |
| 13 | Olive Macdonald | 6 | Daughter | — | Massachusetts |
| 14 | Alfred Byford | 57 | Head | Compositor | England |
| 15 | Mabel Byford | 55 | Wife-H | — | Massachusetts |
| 16 | Bernard Feeney | 36 | Head | Policeman | Massachusetts |
| 17 | Sarah Feeney | 34 | Wife-H | — | Massachusetts |
| 18 | Edward Feeney | 14 | Son | — | Massachusetts |
| 19 | Ruth Feeney | 12 | Daughter | — | Massachusetts |
| 20 | Paul Feeney | 10 | Son | — | Massachusetts |
| 21 | Marguerite Feeney | 8 | Daughter | — | Massachusetts |
| 22 | Leo Feeney | 7 | Son | — | Massachusetts |
| 23 | William Feeney | 4 | Son | — | Massachusetts |
| 24 | Robert Feeney | 2 | Son | — | Massachusetts |
| 25 | Dorothy Feeney | 1 | Daughter | — | Massachusetts |
| 26 | Sarah Davis | 49 | Head-H | — | Canada English |
| 27 | Emma Davis | 23 | Daughter | Office Clerk | Canada English |
| 28 | George Lee | 60 | Head | Porter | England |
| 29 | Elizabeth Lee | 56 | Wife-H | — | England |
| 30 | Sydney Lee | 25 | Son | Radio Operator | Massachusetts |
| 31 | Charles Vassall | 28 | Head | Radio Engineer | Poland |
| 32 | Margaret Vassall | 31 | Wife-H | — | England |
| 33 | Douglas J Vassall | 2 | Son | — | Massachusetts |
| 34 | Joseph Cullia | 34 | Head | Druggist | Massachusetts |
| 35 | Sarah Cullia | 30 | Wife-H | — | Irish Free State |
| 36 | Pauline Cullia | 5 | Daughter | — | Massachusetts |
| 37 | Martha Cullia | 2 | Daughter | — | Massachusetts |
| 38 | John H Mcmahon THIS PERSON | 61 | Head | Sheet Metal Worker | Massachusetts |
| 39 | Annie Mcmahon | 51 | Wife-H | — | Irish Free State |
| 40 | Josephine Mcmahon | 24 | Daughter | Clerk | Massachusetts |
| 41 | Steven A Mcmahon | 53 | Brother | Finisher | Massachusetts |
| 42 | Joseph Mcmahon | 38 | Brother | Salesman | Massachusetts |
| 43 | James A Mcmahon | 34 | Brother | Roofing | Massachusetts |
| 44 | Francis Chaplik | 37 | Head | Chauffeur | Massachusetts |
| 45 | Susan Chaplik | 37 | Wife-H | — | Irish Free State |
| 46 | Francis Chaplik | 5 | Son | — | Massachusetts |
| 47 | Lorraine Chaplik | 1 | Daughter | — | Massachusetts |
| 48 | John Isaulaitis | 58 | Head | Tailor | Lithuania |
| 49 | Catherine Isaulaitis | 55 | Wife-H | — | Lithuania |
| 50 | William H Mahoney | 56 | Head | Laborer | Massachusetts |
About This Record & Model Tree
This record was independently indexed by YourRoots from the 1930 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)