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John Black — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Polk-County, Iowa
Our Model Tree links this John Black across the 1920, 1930 and 1940 US Censuses in Polk-County, Iowa (XGBoost, ~Confirmed) — first a head (b.~1866), then head of a 3-person household.
Age 74
b. ~1866
Male
Head
Born: Ohio
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Polk-County, Iowa |
| Surname | Black |
| Given Name | John |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 74 |
| Marital Status | Married |
| Birthplace | Ohio |
| 1935 Residence (City) | Des Moines City |
| 1935 Residence (County) | Polk |
| Additional Details | |
| Class of Worker | 0 |
| Highest Grade | No 4 |
| 1935 Residence | Same place |
| Birth State | Ohio |
| Birth Country | United States |
| Birthplace (normalized) | ohio |
| Township / Ward | Des Moines City |
| Est. Birth Year | ~1866 |
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 John | Age | Birth yr |
|---|---|---|---|---|
| Mary Beeston | Daughter | — | 31 | ~1909 |
| John Black | Head | — | 74 | ~1866 |
| Mary Black | Spouse | — | 67 | ~1873 |
Census Appearances
1920
Polk, Iowa
Head, age 52
Polk, Iowa · implied b. ~1868 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Black |
| Given Name | John |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 52 |
| Marital Status | Married |
| Birthplace | Ohio |
| Father's Birthplace | Scotland |
| Mother's Birthplace | Scotland |
| Occupation | Engineer |
| Industry | Steam Rail Road |
| Class of Worker | W |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Mother Tongue | Scotch |
| Home Owned/Rented | R |
| Birth State | Ohio |
| Birth Country | United States |
| Birthplace (normalized) | ohio |
1930
Polk, Iowa
Head, age 62
Polk, Iowa · implied b. ~1868 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Black |
| Given Name | John |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 62 |
| Marital Status | Married |
| Birthplace | Ohio |
| Age at First Marriage | 30 |
| Father's Birthplace | Scotland |
| Mother's Birthplace | Scotland |
| Occupation | Loc Engineer |
| Industry | Rail Way |
| Class of Worker | W |
| Can Read/Write | Yes |
| Home Owned/Rented | O |
| Home Value / Rent | 6000 |
| Birth State | Ohio |
| Birth Country | United States |
| Birthplace (normalized) | ohio |
1940
Polk-County, Iowa
Head, age 74
Polk-County, Iowa · implied b. ~1866 — 3 household members
| Surname | Black |
| Given Name | John |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 74 |
| Marital Status | Married |
| Birthplace | Ohio |
| 1935 Residence (City) | Des Moines City |
| 1935 Residence (County) | Polk |
| Class of Worker | 0 |
| Highest Grade | No 4 |
| 1935 Residence | Same place |
| Birth State | Ohio |
| Birth Country | United States |
| Birthplace (normalized) | ohio |
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 Black 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 Black
Head · 1940 · age 74 · b. ~1866 · Iowa
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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 — Polk-County, Iowa
Open full size
1940 US Federal Census — Polk-County, Iowa
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01194-00288)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Russell Brown | 38 | Head | Credit Mgr | Iowa |
| 42 | Grace Brown | 38 | Wife | — | Iowa |
| 43 | Vivian Brown | 16 | Daughter | — | Iowa |
| 44 | Richard Brown | 15 | Son | — | Iowa |
| 45 | Curtis Brown | 6 | Son | — | Iowa |
| 46 | Charles H Pritchard | 39 | Head | Inspector | Iowa |
| 47 | Viola Pritchard | 39 | Wife | — | Iowa |
| 48 | Douglas Pritchard | 19 | Son | Trucker | Iowa |
| 49 | Richard Pritchard | 15 | Son | — | Iowa |
| 50 | Minna Herget | 71 | Mother-in-law | — | Iowa |
| 51 | Jas H Byrnes | 71 | Head | Manager | Illinois |
| 52 | Winifred Byrnes | 28 | Daughter | Clerical | Iowa |
| 53 | Elizabeth Rodgers | 57 | Lodger | Clerical | Iowa |
| 54 | John D Adams | 43 | Head | Sec - Treas | Oklahoma |
| 55 | Laura Adams | 43 | Wife | — | Missouri |
| 56 | Jane Adams | 16 | Daughter | — | Iowa |
| 57 | Ronald H Unick | 50 | Son | Testing Engineer | Iowa |
| 58 | Mary E Unick | 76 | Mother | — | Ireland |
| 59 | Louis Mueller | 52 | Head | Cert. Pub. Acct | Texas |
| 60 | Harriett Mueller | 50 | Wife | — | Ohio |
| 61 | Bette Lou Mueller | 17 | Daughter | — | Iowa |
| 62 | Wendell Bishop | 35 | Head | Partner | Iowa |
| 63 | Margaret Bishop | 29 | Wife | — | Iowa |
| 64 | John Bishop | 3 | Son | — | Iowa |
| 65 | Ellert Brown | 39 | Head | Clerk | Iowa |
| 66 | Naomi Brown | 36 | Wife | — | Iowa |
| 67 | Harriet Boatman | 39 | Lodger | Asst Clerk | Iowa |
| 68 | Claude Mcglothlin | 58 | Head | Photo Engraver | Michigan |
| 69 | Bessie Mcglothlin | 53 | Wife | — | Michigan |
| 70 | Florence Taylor | 35 | Daughter | — | Michigan |
| 71 | William Taylor | 13 | Grandson | — | Iowa |
| 72 | Mary Barr | 62 | Head | Stenographer | Iowa |
| 73 | Charles Davis | 46 | Head | Supervisor | Illinois |
| 74 | Anna Davis | 42 | Wife | — | Iowa |
| 75 | Carl William Messner | 52 | Head | Vice Pres | Iowa |
| 76 | Nelle Messner | 51 | Wife | — | Iowa |
| 77 | Carl Jr Messner | 19 | Son | — | Iowa |
| 78 | John Black THIS PERSON | 74 | Head | — | Ohio |
| 79 | Mary Black | 67 | Wife | — | Ireland |
| 80 | Mary Lou Beeston | 31 | Daughter | — | Iowa |
Related Census Records
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)