FT
Francis Thomas — 1940 US Census Record
Model Tree available1940 United States Federal Census · Marin-County, California
Our Model Tree links this Francis Thomas across the 1920, 1930 and 1940 US Censuses in Marin-County, California (XGBoost, ~Confirmed), with identified parents Frank & Bertha — first a head (b.~1904), then head of a 4-person household.
Age 36
b. ~1904
Male
Head
Born: California
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Marin-County, California |
| Surname | Thomas |
| Given Name | Francis |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 36 |
| Marital Status | Married |
| Birthplace | California |
| 1935 Residence (City) | Bayside Acres |
| 1935 Residence (County) | Marin |
| Additional Details | |
| Occupation | Supt. Mine |
| Industry | Mining |
| Class of Worker | PW |
| Income (1939) | 2000 |
| Highest Grade | H 4 |
| 1935 Residence | Same place |
| Birth State | California |
| Birth Country | United States |
| Birthplace (normalized) | california |
| Occupation | Supt. Mine |
| Township / Ward | Bayside Acres |
| Est. Birth Year | ~1904 |
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 Francis | Age | Birth yr |
|---|---|---|---|---|
| Stella Thomas | Spouse | — | 37 | ~1903 |
| Annette Thomas | Daughter | — | 5 | ~1935 |
| Frances Thomas | Daughter | — | 9 | ~1931 |
| Francis Thomas | Head | — | 36 | ~1904 |
Census Appearances
1920
Marin, California
Son, age 15
Marin, California · implied b. ~1905 — 3 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Thomas |
| Given Name | Francis |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 15 |
| Marital Status | Single |
| Birthplace | California |
| Father's Birthplace | California |
| Mother's Birthplace | California |
| Occupation | none |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | California |
| Birth Country | United States |
| Birthplace (normalized) | california |
1930
Marin, California
Other, age 26
Marin, California · implied b. ~1904 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Thomas |
| Given Name | Francis M. |
| Relationship to Head | O |
| Sex | M |
| Color / Race | White |
| Age | 26 |
| Marital Status | Married |
| Birthplace | California |
| Age at First Marriage | 25 |
| Father's Birthplace | California |
| Mother's Birthplace | California |
| Occupation | Brakeman |
| Industry | Quarry |
| Class of Worker | W |
| Can Read/Write | Yes |
| Home Owned/Rented | 3500 |
| Radio Set | No |
| Birth State | California |
| Birth Country | United States |
| Birthplace (normalized) | california |
1940
Marin-County, California
Head, age 36
Marin-County, California · implied b. ~1904 — 4 household members
| Surname | Thomas |
| Given Name | Francis |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 36 |
| Marital Status | Married |
| Birthplace | California |
| 1935 Residence (City) | Bayside Acres |
| 1935 Residence (County) | Marin |
| Occupation | Supt. Mine |
| Industry | Mining |
| Class of Worker | PW |
| Income (1939) | 2000 |
| Highest Grade | H 4 |
| 1935 Residence | Same place |
| Birth State | California |
| Birth Country | United States |
| Birthplace (normalized) | california |
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 Francis Thomas across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father Frank Thomas (~0.92 confidence) and mother Bertha Thomas (~0.92 confidence). The pedigree spans 1 generation with 2 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
Frank Thomas
b. ~1878
Source father
● Household
· direct · ~0.92
Mother
Bertha Thomas
b. ~1879
Source mother
● Household
· direct · ~0.92
This person
Anchor record
Francis Thomas
Head · 1940 · age 36 · b. ~1904 · California
★ 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 — Marin-County, California
Open full size
1940 US Federal Census — Marin-County, California
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-00262-00022)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Thomas Gray | 70 | Head | Engineer | California |
| 2 | Bertha Gray | 61 | Wife | — | California |
| 3 | Martha Thompson | 62 | Head | Retired | California |
| 4 | Clifford Allman | 66 | Head | Retired | California |
| 5 | Alice Allman | 59 | Wife | — | California |
| 6 | A. P. De Salvo | 42 | Head | Laborer | Azores |
| 7 | A. P. De Salvo | 36 | Son | Engineer | California |
| 8 | Rose De Salvo | 32 | Wife | — | California |
| 9 | Ronald De Salvo | 3 | Son | — | California |
| 10 | Kikuji Matsumoto | 50 | Head | Gardner | Japan |
| 11 | Philip Quito | 58 | Head | Laundryman | Is. Corsica |
| 12 | Margaret Quito | 57 | Wife | Saleslady | Texas |
| 13 | A. G. Campbell | 55 | Head | Gardner | Italy |
| 14 | Marappi Campbell | 58 | Wife | — | Italy |
| 15 | John Milani | 46 | Head | Gardner | Italy |
| 16 | Loren Hurd | 61 | Head | Engineer | Ohio |
| 17 | Laura Hurd | 60 | Wife | — | California |
| 18 | Francis Thomas THIS PERSON | 36 | Head | Supt. Mine | California |
| 19 | Stella Thomas | 37 | Wife | — | Texas |
| 20 | Frances Thomas | 9 | Daughter | — | California |
| 21 | Annette Thomas | 5 | Daughter | — | California |
| 22 | Neil Valdaneu | 49 | Head | Caretaker | Finland |
| 23 | James J. Ach | 49 | Head | — | California |
| 24 | Emma Ach | 44 | Wife | — | Germany |
| 25 | Fred Croker | 64 | Head | Retired | England |
| 26 | Florence Croker | 48 | Wife | Teacher | Nebraska |
| 27 | Rolfe Croker | 15 | Son | — | California |
| 28 | Chas. C. Myers | 68 | Head | Retired | Pennsylvania |
| 29 | Karietta Myers | 57 | Wife | Retired | Pennsylvania |
| 30 | Herman Lewis | 41 | Head | Restaurant | Kansas |
| 31 | Mildred Lewis | 42 | Wife | — | Iowa |
| 32 | Audrey Lewis | 13 | Daughter | — | California |
| 33 | G. M. Burnham | 77 | Head | Retired | Australia |
| 34 | Jessie P. Burnham | 65 | Wife | — | England |
| 35 | Dean Johnson | 51 | Head | Laborer | Sweden |
| 36 | Rose Johnson | 50 | Wife | — | Azores |
| 37 | Sadie Johnson | 21 | Daughter | — | California |
| 38 | Delbert Lunn | 35 | Head | Salesman | Nebraska |
| 39 | Lydia Lunn | 27 | Wife | — | Nebraska |
| 40 | Arman Lunn | 5 | Son | — | Washington |
Pedigree Summary
Francis
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 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)