DC
Donald Clark — 1940 US Census Record
Model Tree available1940 United States Federal Census · Humboldt-County, Iowa
Our Model Tree links this Donald Clark across the 1920, 1930 and 1940 US Censuses in Humboldt-County, Iowa (XGBoost, ~Confirmed), with identified parents Ross & Ross — first a son (b.~1914), then head of a 3-person household.
Age 26
b. ~1914
Male
Son
Born: Iowa
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Humboldt-County, Iowa |
| Surname | Clark |
| Given Name | Donald |
| Relationship to Head | son |
| Sex | M |
| Color / Race | White |
| Age | 26 |
| Marital Status | Single |
| Birthplace | Iowa |
| 1935 Residence (City) | Humboldt Twp |
| 1935 Residence (County) | Humboldt |
| Additional Details | |
| Occupation | farmer |
| Industry | farm |
| Class of Worker | NP |
| Hours Worked | 60 |
| Income (1939) | 0 |
| Highest Grade | Hs 4 |
| 1935 Residence | Same house |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
| Occupation | Farmer |
| Township / Ward | Humboldt Twp |
| Est. Birth Year | ~1914 |
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.
3 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Donald | Age | Birth yr |
|---|---|---|---|---|
| Donald Clark | Son | — | 26 | ~1914 |
| Lulu Clark | Spouse | — | 56 | ~1884 |
| Ross Clark | Head | — | 58 | ~1882 |
Census Appearances
1920
Humboldt, Iowa
Son, age 6
Humboldt, Iowa · implied b. ~1914 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Clark |
| Given Name | Donald |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 6 |
| Marital Status | Single |
| Birthplace | Iowa |
| Father's Birthplace | Iowa |
| Mother's Birthplace | Illinois |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
1930
Humboldt, Iowa
Son, age 16
Humboldt, Iowa · implied b. ~1914 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Clark |
| Given Name | Donald |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 16 |
| Marital Status | Single |
| Birthplace | Iowa |
| Father's Birthplace | Iowa |
| Mother's Birthplace | Iowa |
| Can Read/Write | Yes |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
1940
Humboldt-County, Iowa
Son, age 26
Humboldt-County, Iowa · implied b. ~1914 — 3 household members
| Surname | Clark |
| Given Name | Donald |
| Relationship to Head | son |
| Sex | M |
| Color / Race | White |
| Age | 26 |
| Marital Status | Single |
| Birthplace | Iowa |
| 1935 Residence (City) | Humboldt Twp |
| 1935 Residence (County) | Humboldt |
| Occupation | farmer |
| Industry | farm |
| Class of Worker | NP |
| Hours Worked | 60 |
| Income (1939) | 0 |
| Highest Grade | Hs 4 |
| 1935 Residence | Same house |
| 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 Donald Clark across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father Ross Clark (~0.92 confidence) and father Ross Clark (~0.92 confidence) and mother Edna Clark (~0.92 confidence) and mother Lulu Clark (~0.92 confidence). The pedigree spans 1 generation with 4 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
Ross Clark
b. ~1882
Source father
● Household
· direct · ~0.92
Father
Ross Clark
b. ~1887
Source father
● Household
· direct · ~0.92
Mother
Edna Clark
b. ~1889
Source mother
● Household
· direct · ~0.92
Mother
Lulu Clark
b. ~1884
Source mother
● Household
· direct · ~0.92
This person
Anchor record
Donald Clark
Son · 1940 · age 26 · b. ~1914 · Iowa
★ 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 — Humboldt-County, Iowa
Open full size
1940 US Federal Census — Humboldt-County, Iowa
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01167-00597)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Dorothy Steinman | 19 | step-daughter | Maid | Wisconsin |
| 2 | Charles Hanson | 44 | head | Farmer | Iowa |
| 3 | Lillie Hanson | 48 | sister | — | Iowa |
| 4 | John Johnson | 51 | head | Farmer | Norway |
| 5 | Gusta Johnson | 54 | wife | — | Norway |
| 6 | Glen Johnson | 23 | son | Farm Laborer | Iowa |
| 7 | Lorna Johnson | 17 | daughter | — | Iowa |
| 8 | Gordon Johnson | 15 | son | — | Iowa |
| 9 | Walter Makintosh | 34 | head | Farmer | Iowa |
| 10 | Gladys Makintosh | 32 | wife | — | Iowa |
| 11 | Nancy Makintosh | 4 | daughter | — | Iowa |
| 12 | Phyllis Makintosh | 1 | daughter | — | Iowa |
| 13 | Bernard Fitzgerald | 35 | head | Farmer | Iowa |
| 14 | Agnes Fitzgerald | 35 | wife | — | S Dakota |
| 15 | Maxine Fitzgerald | 11 | daughter | — | Iowa |
| 16 | Bernadine Fitzgerald | 10 | daughter | — | Iowa |
| 17 | James Fitzgerald | 7 | son | — | Iowa |
| 18 | Matt Anderson | 53 | helper | Farm Laborer | Norway |
| 19 | Clarence Wells | 41 | head | Farmer | Iowa |
| 20 | Laura Wells | 40 | wife | — | Iowa |
| 21 | Dela Wells | 18 | daughter | — | Iowa |
| 22 | Olie B. J. Sittler | 46 | head | Farmer | Iowa |
| 23 | Francis Sittler | 78 | mother | — | Illinois |
| 24 | Henry Hagen | 57 | head | Farm Laborer | Iowa |
| 25 | Hilda Hagen | 54 | wife | — | Wisconsin |
| 26 | John Hauck | 32 | head | Farmer | Iowa |
| 27 | Maxine Hauck | 28 | wife | — | Iowa |
| 28 | Charles Lewis Hauck | 6 | son | — | Iowa |
| 29 | Fred Frost | 24 | head | Farmer | Iowa |
| 30 | Pearl Frost | 20 | wife | — | Iowa |
| 31 | Ross H. Clark | 58 | head | Farmer | Iowa |
| 32 | Lulu Clark | 56 | wife | — | Iowa |
| 33 | Donald Clark THIS PERSON | 26 | son | Farmer | Iowa |
| 34 | John Davidson | 67 | head | — | Iowa |
| 35 | Horace Schwanck | 69 | head | — | Minnesota |
| 36 | Rose Schwanck | 66 | wife | — | Iowa |
| 37 | Otto Schwanck | 31 | son | Farmer | Iowa |
| 38 | Rasmus Olsen | 39 | head | Farmer | Iowa |
| 39 | Beth Olsen | 25 | wife | — | Iowa |
| 40 | Laughter Donnormay | 3 | daughter | — | Iowa |
Pedigree Summary
Donald
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)