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John Mcmahon — 1920 US Census Record
Model Tree available1920 United States Federal Census · Merrimack, New Hampshire
Our Model Tree links this John Mcmahon across the 1900, 1910 and 1920 US Censuses in Merrimack, New Hampshire (XGBoost, ~Confirmed), with identified parents Walter & Susan — first a son (b.~1894), then head of a 14-person household.
Age 26
b. ~1894
Male
Son
Born: New Hampshire
Single
1920 Census Record Details
| Census Year | 1920 |
| Location | Merrimack, New Hampshire |
| Surname | McMahon |
| Given Name | John H |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 26 |
| Marital Status | Single |
| Birthplace | New Hampshire |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Additional Details | |
| Occupation | Salesman |
| Industry | Retail Grocery |
| Class of Worker | W |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | New Hampshire |
| Birth Country | United States |
| Birthplace (normalized) | new hampshire |
| Occupation | Salesman |
| Township / Ward | Concord City |
| Est. Birth Year | ~1894 |
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.
14 people recorded at the same address in the 1920 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| Kathleen Mcmahon | Daughter | — | 20 | ~1900 |
| Eleonora Mcmahon | Daughter | — | 9 | ~1911 |
| Bernice Mcmahon | Daughter | — | 21 | ~1899 |
| Blaine Mcmahon | Daughter | — | 13 | ~1907 |
| Pauline Mcmahon | Daughter | — | 11 | ~1909 |
| Margaret Mcmahon | Daughter | — | 15 | ~1905 |
| Agnes Mcmahon | Daughter | — | 28 | ~1892 |
| Mary Mcmahon | Daughter | — | 31 | ~1889 |
| Walter Mcmahon | Head | — | 57 | ~1863 |
| John Mcmahon | Son | — | 26 | ~1894 |
| Edmund Mcmahon | Son | — | 19 | ~1901 |
| Paul Mcmahon | Son | — | 17 | ~1903 |
| Walter Mcmahon | Son | — | 24 | ~1896 |
| Susan Mcmahon | Spouse | — | 51 | ~1869 |
Census Appearances
1900
Merrimack, New …
Son, age 7
Merrimack, New Hampshire · implied b. ~1893 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McMahony |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 6 |
| Marital Status | Single |
| Birthplace | New Hampshire |
| Birth Month | Nov |
| Birth Year | 1893 |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Occupation | At school |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | New Hampshire |
| Birth Country | United States |
| Birthplace (normalized) | new hampshire |
1910
Merrimack, New …
Son, age 16
Merrimack, New Hampshire · implied b. ~1894 — 15 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McMahon |
| Given Name | John J. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 16 |
| Marital Status | Single |
| Birthplace | New Hampshire |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | English |
| Birth State | New Hampshire |
| Birth Country | United States |
| Birthplace (normalized) | new hampshire |
1920
Merrimack, New …
Son, age 26
Merrimack, New Hampshire · implied b. ~1894 — 14 household members
| Surname | McMahon |
| Given Name | John H |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 26 |
| Marital Status | Single |
| Birthplace | New Hampshire |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Occupation | Salesman |
| Industry | Retail Grocery |
| Class of Worker | W |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | New Hampshire |
| Birth Country | United States |
| Birthplace (normalized) | new hampshire |
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 (1900, 1910 and 1920) in Merrimack, New Hampshire, using XGBoost record linkage. Identified parents: father Walter Mcmahon (~0.92 confidence) and mother Susan Mcmahon (~0.92 confidence). The pedigree spans 1 generation with 2 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
Walter Mcmahon
b. ~1863
Source father
● Household
· direct · ~0.92
Mother
Susan Mcmahon
b. ~1869
Source mother
● Household
· direct · ~0.92
This person
Anchor record
John Mcmahon
Son · 1920 · age 26 · b. ~1894 · New Hampshire
★ You are viewing this record
Sibling
Blaine Mcmahon
Sibling · 1920 · age 13
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Mary Mcmahon
Sibling · 1920 · age 31
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Agnes Mcmahon
Sibling · 1920 · age 28
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Kathleen Mcmahon
Sibling · 1920 · age 20
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Margaret Mcmahon
Sibling · 1920 · age 15
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Eleonora Mcmahon
Sibling · 1920 · age 9
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Bernice Mcmahon
Sibling · 1920 · age 21
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Edmund Mcmahon
Sibling · 1920 · age 19
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Paul Mcmahon
Sibling · 1920 · age 17
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Pauline Mcmahon
Sibling · 1920 · age 11
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Walter Mcmahon
Sibling · 1920 · age 24
Source co-child of head (derived)
● Co-child · derived · ~0.88
Confirmed / household (~0.90+)
Probable / derived (~0.65–0.89)
Candidate (<0.65, unverified)
Original Census Page
1920 US Federal Census — Merrimack, New Hampshire
Open full size
1920 US Federal Census — Merrimack, New Hampshire
Page Contents
50 people indexed on this census page (ia:1920:14thcensusofpopu1013unit:0439)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 51 | Mordecai | 4 | Son | — | New Hampshire |
| 52 | Ida | 1 | Daughter | — | New Hampshire |
| 53 | Alaric Long | 47 | Head | Brakeman | Canada |
| 54 | Nellie Long | 41 | Wife | — | Canada |
| 55 | Alphonsine Long | 24 | Daughter | Housekeeper | Canada |
| 56 | Adelle Long | 17 | Daughter | Electrician Worker | Canada |
| 57 | Peter Long | 16 | Son | Laborer | Canada |
| 58 | Rose Long | 14 | Daughter | — | New Hampshire |
| 59 | Delia Long | 9 | Daughter | — | New Hampshire |
| 60 | Antoinette Long | 7 | Daughter | — | New Hampshire |
| 61 | Philip Long | 5 | Son | — | New Hampshire |
| 62 | George Long | 3 | Son | — | New Hampshire |
| 63 | Ernest Long | 2 | Son | — | New Hampshire |
| 64 | John G Holt | 50 | Head | Machinist | New York |
| 65 | Eleanor M Holt | 44 | Wife | — | New Hampshire |
| 66 | Ruth M Holt | 17 | Daughter | — | New Hampshire |
| 67 | Leslie N Holt | 13 | Son | — | New Hampshire |
| 68 | Leon Ahatonneruf | 38 | Head | Car Repair | Canada |
| 69 | Mary Ahatonneruf | 33 | Wife | — | Canada |
| 70 | Marie Ahatonneruf | 14 | Daughter | — | Canada |
| 71 | Armand Ahatonneruf | 5 | Son | — | New Hampshire |
| 72 | Martin Mcmahon | 29 | Head | Cruiser | New Hampshire |
| 73 | Ida S Mcmahon | 25 | Wife | — | New Hampshire |
| 74 | Welch Hannah Mcmahon | 82 | Grandmother | — | Ireland |
| 75 | James H Welch | 49 | Head | — | New Hampshire |
| 76 | Emma Welch | 42 | Wife | — | Vermont |
| 77 | Dorothy M Welch | 14 | Daughter | — | New Hampshire |
| 78 | James H Welch | 12 | Son | — | New Hampshire |
| 79 | Leo A Welch | 10 | Son | — | New Hampshire |
| 80 | Robert F Welch | 7 | Son | — | New Hampshire |
| 81 | Frank P Quimby | 64 | Head | Secretary | New Hampshire |
| 82 | Marie Quimby | 26 | Daughter | — | New Hampshire |
| 83 | Flora M Foote | 51 | Housekeeper | Housekeeper | New Hampshire |
| 84 | Walter Mcmahon | 57 | Head | Car Inspector | Ireland |
| 85 | Susan Mcmahon | 51 | Wife | Housekeeper | Ireland |
| 86 | Mary J Mcmahon | 31 | Daughter | — | New Hampshire |
| 87 | Agnes M Mcmahon | 28 | Daughter | Book Binder | New Hampshire |
| 88 | John H Mcmahon THIS PERSON | 26 | Son | Salesman | New Hampshire |
| 89 | Walter J Mcmahon | 24 | Son | Machinist | New Hampshire |
| 90 | Bernice B Mcmahon | 21 | Daughter | Bookkeeper | New Hampshire |
| 91 | Kathleen Mcmahon | 20 | Daughter | — | New Hampshire |
| 92 | Edmund J Mcmahon | 19 | Son | — | New Hampshire |
| 93 | Paul R Mcmahon | 17 | Son | — | New Hampshire |
| 94 | Margaret N Mcmahon | 15 | Daughter | — | New Hampshire |
| 95 | Blaine Mcmahon | 13 | Daughter | — | New Hampshire |
| 96 | Pauline S Mcmahon | 11 | Daughter | — | New Hampshire |
| 97 | Eleonora Mcmahon | 9 | Daughter | — | New Hampshire |
| 98 | Fred Bean | 42 | Head | Molder | Canada |
| 99 | Emma Bean | 38 | Wife | — | Canada |
| 100 | Alice B Bean | 14 | Daughter | Waitress | Massachusetts |
Related Census Records
Pedigree Summary
John + 11 siblings
Gen 1 · 2 parents
~0.92
Max depth 4 (1900–1950 window)
About This Record & Model Tree
This record was independently indexed by YourRoots from the 1920 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)