MK
Mary Knapp — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Walworth-County, Wisconsin
Our Model Tree links this Mary Knapp across the 1930 and 1940 US Censuses in Walworth-County, Wisconsin (XGBoost, ~Confirmed) — first a daughter (b.~1923), then head of a 6-person household.
Age 17
b. ~1923
Female
Daughter
Born: Wisconsin
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Walworth-County, Wisconsin |
| Surname | Knapp |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 17 |
| Marital Status | Single |
| Birthplace | Wisconsin |
| 1935 Residence (City) | Elkhorn City |
| 1935 Residence (County) | Walworth |
| Additional Details | |
| Income (1939) | 0 |
| Highest Grade | Hs 2 |
| 1935 Residence | Same place |
| Birth State | Wisconsin |
| Birth Country | United States |
| Birthplace (normalized) | wisconsin |
| Township / Ward | Elkhorn City |
| Est. Birth Year | ~1923 |
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 Mary | Age | Birth yr |
|---|---|---|---|---|
| Mary Knapp | Daughter | — | 17 | ~1923 |
| Carol Knapp | Daughter | — | 13 | ~1927 |
| Halbert Knapp | Head | — | 48 | ~1892 |
| Nettie Knapp | Spouse | — | 48 | ~1892 |
| Halbert Knapp | Son | — | 22 | ~1918 |
| Catherine Knapp | Daughter | — | 8 | ~1932 |
Census Appearances
1930
Walworth, Wisconsin
Daughter, age 7
Walworth, Wisconsin · implied b. ~1923 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Knappe |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 7 |
| Marital Status | Single |
| Birthplace | Wisconsin |
| Father's Birthplace | Wisconsin |
| Mother's Birthplace | Wisconsin |
| Occupation | none |
| Can Read/Write | Yes |
| Birth State | Wisconsin |
| Birth Country | United States |
| Birthplace (normalized) | wisconsin |
1940
Walworth-County, Wisconsin
Daughter, age 17
Walworth-County, Wisconsin · implied b. ~1923 — 6 household members
| Surname | Knapp |
| Given Name | Mary |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 17 |
| Marital Status | Single |
| Birthplace | Wisconsin |
| 1935 Residence (City) | Elkhorn City |
| 1935 Residence (County) | Walworth |
| Income (1939) | 0 |
| Highest Grade | Hs 2 |
| 1935 Residence | Same place |
| Birth State | Wisconsin |
| Birth Country | United States |
| Birthplace (normalized) | wisconsin |
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 Mary Knapp across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
Mary Knapp
Daughter · 1940 · age 17 · b. ~1923 · Wisconsin
★ You are viewing this record
Sibling
Catherine Knapp
Sibling · 1940 · age 8
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Carol Knapp
Sibling · 1940 · age 13
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Halbert Knapp
Sibling · 1940 · age 22
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 — Walworth-County, Wisconsin
Open full size
1940 US Federal Census — Walworth-County, Wisconsin
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-04531-00555)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Anna Deining | 41 | Daughter | Book Keeper | Wisconsin |
| 2 | Hilmar Deining | 37 | Son | Proprietor | Wisconsin |
| 3 | Elmer Steffen | 30 | Head | Patrolman | Wisconsin |
| 4 | Wilma Steffen | 29 | Wife | Teacher | Wisconsin |
| 5 | — | None | — | — | — |
| 6 | Fred B. Magill | 62 | Head | Plumber | Wisconsin |
| 7 | Maude P. Magill | 61 | Wife | — | Wisconsin |
| 8 | Willard M. Newman | 32 | Head | Delivery Man | Wisconsin |
| 9 | Esther Newman | 29 | Wife | Teacher | Wisconsin |
| 10 | James Matheson | 46 | Head | Retail Lumberman | Wisconsin |
| 11 | Alfreda Matheson | 31 | Wife | — | Wisconsin |
| 12 | Jean Matheson | 9 | Daughter | — | Wisconsin |
| 13 | Mary Matheson | 8 | Daughter | — | Wisconsin |
| 14 | Bion Ross | 79 | Head | Farmer | Wisconsin |
| 15 | Orpha S. Ross | 74 | Wife | — | Wisconsin |
| 16 | Fannie Hutton | 73 | Head | — | Wisconsin |
| 17 | Francis Hutton | 31 | Son | Farmer | Wisconsin |
| 18 | Bessie Keyes | 57 | Housekeeper | Housekeeper | Wisconsin |
| 19 | Carrie Livingstone | 67 | Head | — | Wisconsin |
| 20 | Harvey Greene | 83 | Lodger | — | Wisconsin |
| 21 | — | None | — | — | — |
| 22 | Willis Lawrence | 28 | Head | General Laborer | Illinois |
| 23 | Emma Lawrence | 27 | Wife | — | Wisconsin |
| 24 | Nancy Jean Lawrence | 5 | Daughter | — | Wisconsin |
| 25 | Linda Lee Lawrence | 0 | Daughter | — | Wisconsin |
| 26 | Jens Christiansen | 38 | Head | Common Laborer | Washington |
| 27 | Ellen Christiansen | 36 | Wife | — | Pennsylvania |
| 28 | Thelma Christiansen | 10 | Daughter | — | Wisconsin |
| 29 | Arthur Scanlon | 59 | Head | — | Wisconsin |
| 30 | Halbert Knapp | 48 | Head | — | Wisconsin |
| 31 | Nettie Knapp | 48 | Wife | — | Wisconsin |
| 32 | Halbert C. Knapp | 22 | Son | New Worker | Wisconsin |
| 33 | Mary Knapp THIS PERSON | 17 | Daughter | — | Wisconsin |
| 34 | Carol Knapp | 13 | Daughter | — | Wisconsin |
| 35 | Catherine Knapp | 8 | Daughter | — | Wisconsin |
| 36 | Carroll Ferge | 21 | Head | Assembler | Wisconsin |
| 37 | Ruby Ferge | 20 | Wife | — | Wisconsin |
| 38 | Richard Kimball | 45 | Head | Maker Of Milk Powder | Wisconsin |
| 39 | Richard Kimball | 14 | Son | — | Wisconsin |
| 40 | Betty Kimball | 11 | Daughter | — | 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)