WK
William Koch — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Bremer-County, Iowa
Our Model Tree links this William Koch across the 1930 and 1940 US Censuses in Bremer-County, Iowa (XGBoost, ~Confirmed) — first a head (b.~1883), then head of a 4-person household.
Age 57
b. ~1883
Male
Head
Born: Michigan
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Bremer-County, Iowa |
| Surname | Koch |
| Given Name | William |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 57 |
| Marital Status | Married |
| Birthplace | Michigan |
| 1935 Residence (City) | Polk Township |
| 1935 Residence (County) | Bremer |
| Additional Details | |
| Occupation | Farmer |
| Industry | Farming |
| Class of Worker | OA |
| Hours Worked | 70 |
| Income (1939) | 0 |
| Highest Grade | No 6 |
| 1935 Residence | Same place |
| Birth State | Michigan |
| Birth Country | United States |
| Birthplace (normalized) | michigan |
| Occupation | Farmer |
| Township / Ward | Polk Township |
| Est. Birth Year | ~1883 |
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 William | Age | Birth yr |
|---|---|---|---|---|
| Edna Koch | Spouse | — | 54 | ~1886 |
| Ralph Koch | Son | — | 25 | ~1915 |
| William Koch | Head | — | 57 | ~1883 |
| Lucille Koch | Daughter | — | 23 | ~1917 |
Census Appearances
1930
Bremer, Iowa
Head, age 47
Bremer, Iowa · implied b. ~1883 — 3 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Koch |
| Given Name | William |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 47 |
| Marital Status | Married |
| Birthplace | Michigan |
| Age at First Marriage | 23 |
| Father's Birthplace | Germany |
| Mother's Birthplace | Germany |
| Occupation | Farmer |
| Industry | General farm |
| Class of Worker | O |
| Can Read/Write | Yes |
| Home Owned/Rented | O |
| Birth State | Michigan |
| Birth Country | United States |
| Birthplace (normalized) | michigan |
1940
Bremer-County, Iowa
Head, age 57
Bremer-County, Iowa · implied b. ~1883 — 4 household members
| Surname | Koch |
| Given Name | William |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 57 |
| Marital Status | Married |
| Birthplace | Michigan |
| 1935 Residence (City) | Polk Township |
| 1935 Residence (County) | Bremer |
| Occupation | Farmer |
| Industry | Farming |
| Class of Worker | OA |
| Hours Worked | 70 |
| Income (1939) | 0 |
| Highest Grade | No 6 |
| 1935 Residence | Same place |
| Birth State | Michigan |
| Birth Country | United States |
| Birthplace (normalized) | michigan |
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 William Koch across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
William Koch
Head · 1940 · age 57 · b. ~1883 · 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 — Bremer-County, Iowa
Open full size
1940 US Federal Census — Bremer-County, Iowa
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01142-00280)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Gordon L. Shipp | 9 | Son | — | Iowa |
| 2 | Galen E. Shipp | 7 | Son | — | Iowa |
| 3 | Minnie Strotman | 77 | Mother-in-law | — | Illinois |
| 4 | Ernest Haase | 48 | Head | Farmer | Iowa |
| 5 | Lillie Haase | 48 | Wife | — | Iowa |
| 6 | Arville Haase | 22 | Son | Farmer | Iowa |
| 7 | Arnold Haase | 20 | Son | Farmer | Iowa |
| 8 | William Koch THIS PERSON | 57 | Head | Farmer | Michigan |
| 9 | Edna Koch | 54 | Wife | — | Iowa |
| 10 | Ralph Koch | 25 | Son | Farmer | Iowa |
| 11 | Lucille Koch | 23 | Daughter | — | Iowa |
| 12 | Emery C. Potter | 53 | Head | Farmer | Iowa |
| 13 | Laura Potter | 50 | Wife | — | Iowa |
| 14 | Claude L. Hastings | 22 | Head | Farmer | Iowa |
| 15 | Frances Hastings | 22 | Wife | — | Iowa |
| 16 | Josephine Jordan | 20 | Lodger | Teacher | Iowa |
| 17 | Harry M. Hartwig | 65 | Head | Farmer | Iowa |
| 18 | Olga Hartwig | 54 | Wife | — | Sweden |
| 19 | Reed L. Carpenter | 64 | Head | Farmer | Ohio |
| 20 | Lottie Carpenter | 57 | Wife | — | Iowa |
| 21 | Lloyd Carpenter | 27 | Head | Farmer | Iowa |
| 22 | Lila Carpenter | 23 | Wife | — | Iowa |
| 23 | David Smith | 29 | Head | Farmer | Iowa |
| 24 | Lucy Smith | 56 | Mother | — | Iowa |
| 25 | Robert Smith | 52 | Father | Farm Laborer | Iowa |
| 26 | Carl Krause | 51 | Head | Farmer | Germany |
| 27 | Hedwig Krause | 50 | Wife | — | Iowa |
| 28 | Gerhardt Krause | 19 | Son | — | Iowa |
| 29 | Herbert Krause | 16 | Son | — | Iowa |
| 30 | Alvin Krause | 14 | Son | — | Iowa |
| 31 | Alfred Krause | 14 | Son | — | Iowa |
| 32 | Irma Krause | 12 | Daughter | — | Iowa |
| 33 | William Ruth | 37 | Head | Farmer | Nebraska |
| 34 | Cora Ruth | 27 | Wife | — | Iowa |
| 35 | Wilma Ruth | 8 | Daughter | — | Iowa |
| 36 | Walter J. Ruth | 12 | Son | — | Iowa |
| 37 | John W. Steere | 50 | Head | Farmer | Iowa |
| 38 | Viola Steere | 42 | Wife | — | Iowa |
| 39 | Raymond D. Steere | 22 | Son | Farm Laborer | Iowa |
| 40 | Velma Steere | 20 | Daughter | — | Iowa |
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)