JN
John Nichols — 1940 US Census Record
Model Tree available1940 United States Federal Census · Clinton-County, Iowa
Our Model Tree links this John Nichols across the 1920, 1930 and 1940 US Censuses in Clinton-County, Iowa (XGBoost, ~Confirmed), with identified parents William & William — first a son (b.~1914), then head of a 6-person household.
Age 26
b. ~1914
Male
Son
Born: Iowa
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Clinton-County, Iowa |
| Surname | Nichols |
| Given Name | John R. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 26 |
| Marital Status | Single |
| Birthplace | Iowa |
| 1935 Residence (City) | Clinton City |
| 1935 Residence (County) | Clinton |
| Additional Details | |
| Occupation | Laborer |
| Industry | Building Construction |
| Class of Worker | PW |
| Hours Worked | 52 |
| Income (1939) | 0 |
| Highest Grade | 8 |
| 1935 Residence | Same House |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
| Occupation | Laborer |
| Township / Ward | Clinton City |
| 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.
6 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| Marie Nichols | Daughter | — | 32 | ~1908 |
| Alma Nichols | Daughter | — | 18 | ~1922 |
| Mardell Nichols | Daughter | — | 24 | ~1916 |
| William Nichols | Head | — | 73 | ~1867 |
| John Nichols | Son | — | 26 | ~1914 |
| Sadie Nichols | Spouse | — | 60 | ~1880 |
Census Appearances
1920
Clinton, Iowa
Son, age 6
Clinton, Iowa · implied b. ~1914 — 9 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Nichols |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 6 |
| Marital Status | Single |
| Birthplace | Iowa |
| Father's Birthplace | Ohio |
| Mother's Birthplace | Iowa |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
1930
Clinton, Iowa
Son, age 16
Clinton, Iowa · implied b. ~1914 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Nichols |
| Given Name | John R. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 16 |
| Marital Status | Single |
| Birthplace | Iowa |
| Father's Birthplace | Ohio |
| Mother's Birthplace | Iowa |
| Can Read/Write | Yes |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
1940
Clinton-County, Iowa
Son, age 26
Clinton-County, Iowa · implied b. ~1914 — 6 household members
| Surname | Nichols |
| Given Name | John R. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 26 |
| Marital Status | Single |
| Birthplace | Iowa |
| 1935 Residence (City) | Clinton City |
| 1935 Residence (County) | Clinton |
| Occupation | Laborer |
| Industry | Building Construction |
| Class of Worker | PW |
| Hours Worked | 52 |
| Income (1939) | 0 |
| Highest Grade | 8 |
| 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 John Nichols across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father William Nichols (~0.92 confidence) and father William Nichols (~0.92 confidence) and mother Sadie Nichols (~0.92 confidence). The pedigree spans 1 generation with 3 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
William Nichols
b. ~1867
Source father
● Household
· direct · ~0.92
Father
William Nichols
b. ~1868
Source father
● Household
· direct · ~0.92
Mother
Sadie Nichols
b. ~1880
Source mother
● Household
· direct · ~0.92
This person
Anchor record
John Nichols
Son · 1940 · age 26 · b. ~1914 · Iowa
★ You are viewing this record
Sibling
Marie Nichols
Sibling · 1940 · age 32
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Alma Nichols
Sibling · 1940 · age 18
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Mardell Nichols
Sibling · 1940 · age 24
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 — Clinton-County, Iowa
Open full size
1940 US Federal Census — Clinton-County, Iowa
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01150-00705)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Bernice Carson | 21 | Servant | Maid | Iowa |
| 42 | Rodney S. Olney | 48 | Head | Telegraph | Iowa |
| 43 | Clara S. Olney | 53 | Wife | — | Iowa |
| 44 | Arnold J. Holle | 33 | Head | Laborer | Iowa |
| 45 | Estelle L. Holle | 31 | Wife | — | Illinois |
| 46 | Jacqueline J. Holle | 9 | Daughter | — | Iowa |
| 47 | Mary Phillips | 61 | Head | — | Iowa |
| 48 | Paul H. Wittekind | 35 | Head | Salesman | Iowa |
| 49 | Eleanor Wittekind | 25 | Wife | — | Iowa |
| 50 | Paula J. Wittekind | 5 | Daughter | — | Iowa |
| 51 | Natalie A. Wittekind | 2 | Daughter | — | Iowa |
| 52 | Lawrence A. Gladhill | 38 | Head | Shipping Clerk | Illinois |
| 53 | Merle M. Gladhill | 28 | Brother | Salesman | Iowa |
| 54 | Sarah S. Nelson | 66 | Housekeeper | Housekeeper | Illinois |
| 55 | Clarence A. Messinger | 46 | Head | Yardman | Nebraska |
| 56 | Vera A. Messinger | 40 | Wife | — | Illinois |
| 57 | Paul R. Messinger | 22 | Son | Stock Clerk | Illinois |
| 58 | Conrad Hensen | 48 | Head | Sander | Germany |
| 59 | Marie Hensen | 43 | Wife | — | Germany |
| 60 | Jr Conrad Hensen | 18 | Son | Truck Driver | Minnesota |
| 61 | Johanna Hensen | 17 | Daughter | — | Minnesota |
| 62 | Hiram Holt | 30 | Head | Keep Helper | Iowa |
| 63 | Annetta Holt | 35 | Wife | Egg Candler | Illinois |
| 64 | Bessie M. Cave | 16 | Daughter | — | Iowa |
| 65 | Audrey P. Cave | 12 | Daughter | — | Iowa |
| 66 | Alice May Holt | 4 | Daughter | — | Iowa |
| 67 | Charles A. Evans | 63 | Head | Piano Tuner | Iowa |
| 68 | Rose Anna Evans | 47 | Wife | — | Iowa |
| 69 | Earl Evans | 25 | Son | Laborer | Iowa |
| 70 | William C. Nichols | 73 | Head | — | Ohio |
| 71 | Sadie E. Nichols | 60 | Wife | — | Iowa |
| 72 | Marie M. Nichols | 32 | Daughter | Clerk | Iowa |
| 73 | Mardell S. Nichols | 24 | Daughter | Clerk | Iowa |
| 74 | John R. Nichols THIS PERSON | 26 | Son | Laborer | Iowa |
| 75 | Alma H. Nichols | 18 | Daughter | — | Iowa |
| 76 | John H. Kreb | 70 | Head | — | Iowa |
| 77 | Minnie Kreb | 76 | Wife | — | Germany |
| 78 | Marjorie Kreb | 53 | Daughter | — | Iowa |
| 79 | Kate Carstensen | 62 | Head | — | Iowa |
| 80 | Melinda Carstensen | 24 | Daughter | Nurse | Iowa |
Pedigree Summary
John + 3 siblings
Gen 1 · 3 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)