HT
Harold Thomas — 1940 US Census Record
Model Tree available1940 United States Federal Census · Jefferson-County, Iowa
Our Model Tree links this Harold Thomas across the 1920, 1930 and 1940 US Censuses in Jefferson-County, Iowa (XGBoost, ~Confirmed), with identified parents William & William — first a son (b.~1901), then head of a 4-person household.
Age 39
b. ~1901
Male
Son
Born: Iowa
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Jefferson-County, Iowa |
| Surname | Thomas |
| Given Name | Harold |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 39 |
| Marital Status | Single |
| Birthplace | Iowa |
| 1935 Residence (City) | R |
| 1935 Residence (County) | Jefferson |
| Additional Details | |
| Occupation | Laborer |
| Industry | Farming |
| Class of Worker | E |
| Hours Worked | 36 |
| Income (1939) | 866 |
| Highest Grade | H 4 |
| 1935 Residence | Iowa |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
| Occupation | Laborer |
| Township / Ward | Center |
| Est. Birth Year | ~1901 |
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 Harold | Age | Birth yr |
|---|---|---|---|---|
| Dorothy Thomas | Spouse | — | 62 | ~1878 |
| W Thomas | Son | — | 29 | ~1911 |
| W Thomas | Head | — | 64 | ~1876 |
| Harold Thomas | Son | — | 39 | ~1901 |
Census Appearances
1920
Jefferson, Iowa
Son, age 20
Jefferson, Iowa · implied b. ~1900 — 8 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Thoma |
| Given Name | Harold B. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 20 |
| Marital Status | Single |
| Birthplace | Iowa |
| Father's Birthplace | Iowa |
| Mother's Birthplace | Iowa |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
1930
Jefferson, Iowa
Son, age 29
Jefferson, Iowa · implied b. ~1901 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Thoma |
| Given Name | Harold |
| Relationship to Head | son |
| Sex | M |
| Color / Race | White |
| Age | 29 |
| Marital Status | Single |
| Birthplace | Iowa |
| Father's Birthplace | Iowa |
| Mother's Birthplace | Iowa |
| Occupation | laborer |
| Industry | Gen. farm |
| Class of Worker | W |
| Can Read/Write | Yes |
| Home Owned/Rented | W |
| Home Value / Rent | no |
| Radio Set | 2 |
| Veteran | no |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
1940
Jefferson-County, Iowa
Son, age 39
Jefferson-County, Iowa · implied b. ~1901 — 4 household members
| Surname | Thomas |
| Given Name | Harold |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 39 |
| Marital Status | Single |
| Birthplace | Iowa |
| 1935 Residence (City) | R |
| 1935 Residence (County) | Jefferson |
| Occupation | Laborer |
| Industry | Farming |
| Class of Worker | E |
| Hours Worked | 36 |
| Income (1939) | 866 |
| Highest Grade | H 4 |
| 1935 Residence | Iowa |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
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 Harold Thomas across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father William Thoma (~0.92 confidence) and father William Thoma (~0.92 confidence) and father W Thomas (~0.92 confidence) and mother Dorothea Thoma (~0.92 confidence). The pedigree spans 1 generation with 4 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
William Thoma
b. ~1873
Source father
● Household
· direct · ~0.92
Father
William Thoma
b. ~1875
Source father
● Household
· direct · ~0.92
Father
W Thomas
b. ~1876
Source father
● Household
· direct · ~0.92
Mother
Dorothea Thoma
b. ~1878
Source mother
● Household
· direct · ~0.92
This person
Anchor record
Harold Thomas
Son · 1940 · age 39 · b. ~1901 · Iowa
★ You are viewing this record
Sibling
W Thomas
Sibling · 1940 · age 29
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
1940 US Federal Census — Jefferson-County, Iowa
Open full size
1940 US Federal Census — Jefferson-County, Iowa
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01170-00063)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Frank Brown | 35 | Head | Farmer | Illinois |
| 42 | Baker S. Brown | 57 | Uncle | Farmer | Illinois |
| 43 | Basil Messer | 37 | Head | Farmer | Iowa |
| 44 | Addie Messer | 35 | Wife | — | Iowa |
| 45 | Josephine Messer | 11 | Daughter | — | Iowa |
| 46 | Rance Elder | 57 | Head | Laborer | Iowa |
| 47 | Charley W. Elder | 36 | Son | N.P.S. Engineer | Iowa |
| 48 | Paul Simmons | 57 | Head | Trucker | Iowa |
| 49 | Charles Duggan | 23 | Head | Oil Stat Attendant | Iowa |
| 50 | Ben Murphy | 24 | Brother in law | Painter | Iowa |
| 51 | Irene Murphy | 20 | Sister | — | Iowa |
| 52 | Grover Mcclain | 50 | Head | Farmer | Iowa |
| 53 | Hazel Mcclain | 48 | Wife | — | Iowa |
| 54 | John D. Paxton | 41 | Head | Farmer | Iowa |
| 55 | Marie Paxton | 35 | Wife | — | Iowa |
| 56 | Wilbur Paxton | 16 | Son | Laborer | Iowa |
| 57 | Eva May Paxton | 14 | Daughter | — | Iowa |
| 58 | Gilbert Paxton | 12 | Son | — | Iowa |
| 59 | John R. Paxton | 9 | Son | — | Iowa |
| 60 | Harold Paxton | 6 | Son | — | Iowa |
| 61 | Joan Paxton | 3 | Daughter | — | Iowa |
| 62 | Carroll Jarvis | 24 | Head | Carpenter | Iowa |
| 63 | Virginia Jarvis | 26 | Wife | — | Iowa |
| 64 | Jerry Jarvis | 1 | Son | — | Iowa |
| 65 | W. H. Thomas | 64 | Head | — | Iowa |
| 66 | Dorothy Thomas | 62 | Wife | Waitress | Iowa |
| 67 | Harold Thomas THIS PERSON | 39 | Son | Laborer | Iowa |
| 68 | W. H. Jr. Thomas | 29 | Son | Janitor | Iowa |
| 69 | Earl Field | 33 | Head | Farmer | Iowa |
| 70 | Helen Field | 25 | Wife | — | Iowa |
| 71 | Robert W. Field | 10 | Son | — | Iowa |
| 72 | Ida Belle Field | 8 | Daughter | — | Iowa |
| 73 | Mary Lou Field | 1 | Daughter | — | Iowa |
| 74 | Isabella Hutton | 77 | Head | — | Iowa |
| 75 | John Hutton | 42 | Son | Laborer | Iowa |
| 76 | Mable Hughes | 55 | Daughter | — | Iowa |
| 77 | Josephine Hughes | 16 | Granddaughter | — | Iowa |
| 78 | Lester Ruger | 25 | Head | Laborer | Missouri |
| 79 | Velma Ruger | 17 | Wife | — | Iowa |
| 80 | Lester Jr. Ruger | 0 | Son | — | Iowa |
Related Census Records
Pedigree Summary
Harold + 1 sibling
Gen 1 · 4 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)