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John Mcgrath — 1940 US Census Record
Linked across censuses1940 United States Federal Census · San-Mateo-County, California
Our Model Tree links this John Mcgrath across the 1920, 1930 and 1940 US Censuses in San-Mateo-County, California (XGBoost, ~Confirmed) — first a head (b.~1874), then head of a 5-person household.
Age 66
b. ~1874
Male
Head
Born: Ireland
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | San-Mateo-County, California |
| Surname | McGrath |
| Given Name | John J. |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 66 |
| Marital Status | Married |
| Birthplace | Ireland |
| 1935 Residence (City) | Washington |
| 1935 Residence (County) | D.C. |
| Naturalization Status | Naturalized |
| Additional Details | |
| Occupation | Commissioner |
| Industry | Immigration |
| Class of Worker | GW |
| Hours Worked | 44 |
| Income (1939) | 5600 |
| Highest Grade | No |
| 1935 Residence | Same place |
| Birth Country | Ireland |
| Birthplace (normalized) | ireland |
| Occupation | Commissioner |
| Township / Ward | Hillsborough Town |
| Est. Birth Year | ~1874 |
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.
5 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| Maureen Partlow | Daughter | — | 30 | ~1910 |
| John Mcgrath | Head | — | 66 | ~1874 |
| Francis Lewis | Other | — | 21 | ~1919 |
| William Partlow | Other | — | 35 | ~1905 |
| Mary Mcgrath | Spouse | — | 21 | ~1919 |
Census Appearances
1920
San Francisco, …
Other, age 45
San Francisco, California · implied b. ~1875 — 50 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | McGrath |
| Given Name | John |
| Relationship to Head | Lodger |
| Sex | M |
| Color / Race | White |
| Age | 45 |
| Marital Status | Single |
| Birthplace | Ireland |
| Year of Immigration | 1890 |
| Naturalization Status | Naturalized |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Occupation | Waiter |
| Industry | Restaurant |
| Class of Worker | W |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Mother Tongue | Irish |
| Birth Country | Ireland |
| Year of Naturalization | 1896 |
| Birthplace (normalized) | ireland |
1930
San Francisco, …
Head, age 57
San Francisco, California · implied b. ~1873
●
Primary link
· ~Confirmed · 1 source
XGBoost
| Surname | McGrath |
| Given Name | John |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 57 |
| Marital Status | Married |
| Birthplace | Ireland |
| Naturalization Status | Naturalized |
| Year of Immigration | 1890 |
| Age at First Marriage | 27 |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Can Read/Write | Yes |
| Mother Tongue | English |
| Home Owned/Rented | R |
| Home Value / Rent | 25 |
| Radio Set | R |
| Birth Country | Ireland |
| Birthplace (normalized) | ireland |
1940
San-Mateo-County, California
Head, age 66
San-Mateo-County, California · implied b. ~1874 — 5 household members
| Surname | McGrath |
| Given Name | John J. |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 66 |
| Marital Status | Married |
| Birthplace | Ireland |
| 1935 Residence (City) | Washington |
| 1935 Residence (County) | D.C. |
| Naturalization Status | Naturalized |
| Occupation | Commissioner |
| Industry | Immigration |
| Class of Worker | GW |
| Hours Worked | 44 |
| Income (1939) | 5600 |
| Highest Grade | No |
| 1935 Residence | Same place |
| 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 John 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
John Mcgrath
Head · 1940 · age 66 · b. ~1874 · California
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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 — San-Mateo-County, California
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1940 US Federal Census — San-Mateo-County, California
Page Contents
21 people indexed on this census page (nara:1940:m-t0627-00330-00120)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | John J. Mcgrath THIS PERSON | 66 | Head | Commissioner | Ireland |
| 2 | Mary A. Mcgrath | 21 | Wife | — | California |
| 3 | William Partlow | 35 | Son-in-law | Clerk | Washington D.C. |
| 4 | Maureen Partlow | 30 | Daughter | — | California |
| 5 | Francis Lewis | 21 | Maid | — | California |
| 6 | Thomas M. Lightfoot | 74 | Head | — | Pennsylvania |
| 7 | John Magee | 73 | Head | — | New York |
| 8 | Florence Magee | 61 | Wife | — | New York |
| 9 | Julia Savage | 59 | Housekeeper | Housekeeper | New York |
| 10 | Louise Hard | 30 | Maid | Servant | England |
| 11 | Robert Gaecke | 54 | Butler | Servant | Germany |
| 12 | Ernest Plant | 51 | Butler | Servant | England |
| 13 | Harry Rhea | 35 | Chauffeur | Chauffeur | France |
| 14 | Bertha Chagloie | 53 | Maid | Servant | Denmark |
| 15 | Hans Hansen | 53 | Gardener | Gardener | Denmark |
| 16 | Regine Hansen | 53 | Cook | Servant | Denmark |
| 17 | Marguerite O'Brien | 52 | Head | — | — |
| 18 | Charles S. Howard | 63 | Head | Corporation Executive | Georgia |
| 19 | Marcella Howard | 36 | Wife | — | California |
| 20 | Lingon G. Warren | 50 | Head | Corporation Pres. | Virginia |
| 21 | Sara S. Warren | 47 | Wife | — | Florida |
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)