RA
Robert Armstrong — 1940 US Census Record
Model Tree available1940 United States Federal Census · Douglas-County, Illinois
Our Model Tree links this Robert Armstrong across the 1920, 1930 and 1940 US Censuses in Douglas-County, Illinois (XGBoost, ~Confirmed), with identified parents Lloyd & Kathryn — first a son (b.~1916), then head of a 9-person household.
Age 24
b. ~1916
Male
Son
Born: Illinois
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Douglas-County, Illinois |
| Surname | Armstrong |
| Given Name | Robert B. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 24 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Sargent |
| 1935 Residence (County) | Douglas |
| Additional Details | |
| Occupation | Farmer |
| Industry | Farmhand |
| Class of Worker | PW |
| Hours Worked | 60 |
| Income (1939) | 360 |
| Highest Grade | H-3 |
| 1935 Residence | Same house |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Occupation | Farmer |
| Township / Ward | Sargent |
| Est. Birth Year | ~1916 |
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.
9 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Robert | Age | Birth yr |
|---|---|---|---|---|
| Jessie Armstrong | Daughter | — | 21 | ~1919 |
| Floyd Armstrong | Head | — | 22 | ~1918 |
| Donald Armstrong | Son | — | 11 | ~1929 |
| Arthur Armstrong | Son | — | 28 | ~1912 |
| Archie Armstrong | Son | — | 18 | ~1922 |
| John Armstrong | Son | — | 26 | ~1914 |
| Robert Armstrong | Son | — | 24 | ~1916 |
| Lloyd Armstrong | Son | — | 20 | ~1920 |
| Katherine Armstrong | Spouse | — | 19 | ~1921 |
Census Appearances
1920
Douglas, Illinois
Son, age 4
Douglas, Illinois · implied b. ~1916 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Armstrong |
| Given Name | Robert B. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 4 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Illinois |
| Mother's Birthplace | Illinois |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1930
Douglas, Illinois
Son, age 14
Douglas, Illinois · implied b. ~1916 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Armstrong |
| Given Name | Robert D. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 14 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Illinois |
| Mother's Birthplace | Illinois |
| Can Read/Write | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Douglas-County, Illinois
Son, age 24
Douglas-County, Illinois · implied b. ~1916 — 9 household members
| Surname | Armstrong |
| Given Name | Robert B. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 24 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Sargent |
| 1935 Residence (County) | Douglas |
| Occupation | Farmer |
| Industry | Farmhand |
| Class of Worker | PW |
| Hours Worked | 60 |
| Income (1939) | 360 |
| Highest Grade | H-3 |
| 1935 Residence | Same house |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
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 Robert Armstrong across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father Lloyd Armstrong (~0.92 confidence) and mother Kathryn Armstrong (~0.92 confidence) and mother Opal Armstrong (~0.92 confidence) and father Floyd Armstrong (~0.50 confidence) and mother Katherine Armstrong (~0.50 confidence). The pedigree spans 1 generation with 5 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.75
Father
Lloyd Armstrong
b. ~1890
Source father
● Household
· direct · ~0.92
Mother
Kathryn Armstrong
b. ~1891
Source mother
● Household
· direct · ~0.92
Mother
Opal Armstrong
b. ~1891
Source mother
● Household
· direct · ~0.92
Father
Floyd Armstrong
b. ~1918
Source father
● Household
· direct · ~0.5
Mother
Katherine Armstrong
b. ~1921
Source mother
● Household
· direct · ~0.5
This person
Anchor record
Robert Armstrong
Son · 1940 · age 24 · b. ~1916 · Illinois
★ You are viewing this record
Sibling
Donald Armstrong
Sibling · 1940 · age 11
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Arthur Armstrong
Sibling · 1940 · age 28
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Archie Armstrong
Sibling · 1940 · age 18
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Lloyd Armstrong
Sibling · 1940 · age 20
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Jessie Armstrong
Sibling · 1940 · age 21
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
John Armstrong
Sibling · 1940 · age 26
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 — Douglas-County, Illinois
Open full size
1940 US Federal Census — Douglas-County, Illinois
Page Contents
21 people indexed on this census page (nara:1940:m-t0627-00795-00261)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Mary E. Breen | 24 | Wife | — | Illinois |
| 42 | Charles Jr. Breen | 3 | Son | — | Illinois |
| 43 | Mary J. Breen | 2 | Daughter | — | Illinois |
| 44 | Judith C. Breen | 1 | Daughter | — | Illinois |
| 45 | Floyd A. Armstrong | 22 | Head | Farmer | Illinois |
| 46 | Katherine R. Armstrong | 19 | Wife | — | Illinois |
| 47 | Arthur R. Armstrong | 28 | Son | Farmer | Illinois |
| 48 | John J. Armstrong | 26 | Son | Farmer | Illinois |
| 49 | Robert B. Armstrong THIS PERSON | 24 | Son | Farmer | Illinois |
| 50 | Jessie E. Armstrong | 21 | Daughter | Stenographer | Illinois |
| 51 | Lloyd L. Armstrong | 20 | Son | Farmer | Illinois |
| 52 | Archie D. Armstrong | 18 | Son | — | Illinois |
| 53 | Donald F. Armstrong | 11 | Son | — | Illinois |
| 54 | Arlie A. Cruzan | 57 | Head | Farmer | Illinois |
| 55 | Bessie I. Cruzan | 46 | Wife | — | Kentucky |
| 56 | Mildred L. Cruzan | 22 | Daughter | Farmer | Illinois |
| 57 | Floyd A. Cruzan | 20 | Son | Farmer | Illinois |
| 58 | John R. Cruzan | 16 | Son | — | Illinois |
| 59 | Dorothy J. Cruzan | 9 | Daughter | — | Illinois |
| 60 | Robert W. Cruzan | 6 | Son | — | Illinois |
| 61 | Bedford Vanwinkle | 67 | Uncle | — | Kentucky |
Pedigree Summary
Robert + 6 siblings
Gen 1 · 5 parents
~0.75
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)