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John Koch — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Milwaukee-County, Wisconsin
Our Model Tree links this John Koch across the 1920, 1930 and 1940 US Censuses in Milwaukee-County, Wisconsin (XGBoost, ~Confirmed) — first a head (b.~1888), then head of a 6-person household.
Age 52
b. ~1888
Male
Head
Born: Hungary
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Milwaukee-County, Wisconsin |
| Surname | Koch |
| Given Name | John |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 52 |
| Marital Status | Married |
| Birthplace | Hungary |
| 1935 Residence (City) | Milwaukee City |
| 1935 Residence (County) | Milwaukee |
| Naturalization Status | Naturalized |
| Additional Details | |
| Occupation | Crane Repair |
| Industry | Steel Mill |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 336 |
| Highest Grade | No 8 |
| 1935 Residence | Same House |
| Birth Country | Hungary |
| Birthplace (normalized) | hungary |
| Occupation | Crane Repair |
| Township / Ward | Milwaukee City |
| Est. Birth Year | ~1888 |
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.
6 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| Elizabeth Koch | Spouse | — | 43 | ~1897 |
| Cecelia Koch | Daughter | — | 25 | ~1915 |
| Gary Koch | Other | — | 4 | ~1936 |
| Cynthia Koch | Other | — | 1 | ~1939 |
| John Koch | Son | — | 21 | ~1919 |
| John Koch | Head | — | 52 | ~1888 |
Census Appearances
1920
Hennepin, Minnesota
Head, age 31
Hennepin, Minnesota · implied b. ~1889 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Koch |
| Given Name | John |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 31 |
| Marital Status | Married |
| Birthplace | Hungary |
| Year of Immigration | 1906 |
| Naturalization Status | First papers filed |
| Father's Birthplace | Hungary |
| Mother's Birthplace | Hungary |
| Occupation | Molder |
| Industry | Foundry |
| Class of Worker | W |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Mother Tongue | German |
| Home Owned/Rented | R |
| Birth Country | Hungary |
| Birthplace (normalized) | hungary |
1930
Milwaukee, Wisconsin
Head, age 42
Milwaukee, Wisconsin · implied b. ~1888 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Koch |
| Given Name | John |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 42 |
| Marital Status | Married |
| Birthplace | Hungary |
| Naturalization Status | Naturalized |
| Year of Immigration | 1906 |
| Age at First Marriage | 21 |
| Father's Birthplace | Hungary |
| Mother's Birthplace | Hungary |
| Occupation | Millwright |
| Industry | Tractor plant |
| Class of Worker | W |
| Can Read/Write | Yes |
| Mother Tongue | German |
| Home Owned/Rented | O |
| Home Value / Rent | 8000 |
| Veteran | No |
| Birth Country | Hungary |
| Birthplace (normalized) | hungary |
1940
Milwaukee-County, Wisconsin
Head, age 52
Milwaukee-County, Wisconsin · implied b. ~1888 — 6 household members
| Surname | Koch |
| Given Name | John |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 52 |
| Marital Status | Married |
| Birthplace | Hungary |
| 1935 Residence (City) | Milwaukee City |
| 1935 Residence (County) | Milwaukee |
| Naturalization Status | Naturalized |
| Occupation | Crane Repair |
| Industry | Steel Mill |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 336 |
| Highest Grade | No 8 |
| 1935 Residence | Same House |
| Birth Country | Hungary |
| Birthplace (normalized) | hungary |
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 Koch across 3 US Census years (1920, 1930 and 1940) in 3 locations, using XGBoost record linkage.
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This person
Anchor record
John Koch
Head · 1940 · age 52 · b. ~1888 · Wisconsin
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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 — Milwaukee-County, Wisconsin
Open full size
1940 US Federal Census — Milwaukee-County, Wisconsin
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-04556-00293)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Matt Vilovic | 55 | Head | Proprietor | Austria |
| 42 | Johanna Vilovic | 40 | Wife | Kitchen Help | Austria |
| 43 | John Koch THIS PERSON | 52 | Head | Crane Repair | Hungary |
| 44 | Elizabeth Koch | 43 | Wife | Enamel Dipper | Hungary |
| 45 | John Jr. Koch | 21 | Son | Attendant | Wisconsin |
| 46 | Cecelia Koch | 25 | Daughter | — | Wisconsin |
| 47 | Gary Koch | 4 | Grandson | — | Wisconsin |
| 48 | Cynthia Koch | 1 | Granddaughter | — | Wisconsin |
| 49 | John Schwerly | 32 | Head | Truck Driver | Hungary |
| 50 | Agnes Schwerly | 25 | Wife | — | Wisconsin |
| 51 | Catherine Schwerly | 4 | Daughter | — | Wisconsin |
| 52 | John Schwerly | 1 | Son | — | Wisconsin |
| 53 | George Mahn | 31 | Head | Machinist | Wisconsin |
| 54 | Elizabeth Mahn | 21 | Wife | — | Illinois |
| 55 | George P. Mahn | 7 | Son | — | Wisconsin |
| 56 | James R. Mahn | 2 | Son | — | Wisconsin |
| 57 | Phillip Lemondowski | 29 | Head | Laborer | Illinois |
| 58 | Dorothy Lemondowski | 29 | Wife | — | Wisconsin |
| 59 | Herbert Lemondowski | 6 | Son | — | Wisconsin |
| 60 | Joseph Lemondowski | 5 | Son | — | Wisconsin |
| 61 | William Albrecht | 35 | Brother-in-law | Salesman | Wisconsin |
| 62 | John Stetler | 37 | Head | Riveter | Hungary |
| 63 | Lorraine Stetler | 38 | Wife | — | Wisconsin |
| 64 | Gloria Ann Stetler | 13 | Daughter | — | Wisconsin |
| 65 | Jack Stetler | 11 | Son | — | Wisconsin |
| 66 | Robert Stetler | 6 | Son | — | Wisconsin |
| 67 | Martin Jacobson | 59 | Head | Drafting Engineer | Iowa |
| 68 | Marie Jacobson | 57 | Wife | — | Norway |
| 69 | Laverne Fahrenberg | 24 | Daughter | Stenographer | Wisconsin |
| 70 | Robert Fahrenberg | 28 | Son-in-law | Salesman | Wisconsin |
| 71 | Ira J. Griffin | 40 | Head | Locomotive Engineer | Wisconsin |
| 72 | Rose Griffin | 33 | Wife | — | Michigan |
| 73 | Marjorie Griffin | 11 | Daughter | — | Wisconsin |
| 74 | Richard Griffin | 9 | Son | — | Washington |
| 75 | Alex Pleegatz | 52 | Head | Molder | Austria |
| 76 | Eva Pleegatz | 44 | Wife | — | Austria |
| 77 | William Pleegatz | 23 | Son | — | Wisconsin |
| 78 | Steve Pleegatz | 22 | Son | — | Wisconsin |
| 79 | John Pleegatz | 20 | Son | New Worker | Wisconsin |
| 80 | W. O. Puehling | 50 | Head | Salesman | Wisconsin |
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)