MH
Mary Harper — 1940 US Census Record
Model Tree available1940 United States Federal Census · Rock-Island-County, Illinois
Our Model Tree links this Mary Harper across the 1920, 1930 and 1940 US Censuses in Rock-Island-County, Illinois (XGBoost, ~Confirmed), with identified parents Cecil & Minnie — first a daughter (b.~1918), then head of a 5-person household.
Age 22
b. ~1918
Female
Daughter
Born: Illinois
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Rock-Island-County, Illinois |
| Surname | Harper |
| Given Name | Mary Kathryn |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 22 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Silvis City |
| 1935 Residence (County) | Rock Island |
| Additional Details | |
| Occupation | Laborer |
| Industry | Rubber Shoe Co |
| Class of Worker | PW |
| Hours Worked | 4 |
| Income (1939) | 765 |
| Highest Grade | Hs 4 |
| 1935 Residence | Same place |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Occupation | Laborer |
| Township / Ward | Silvis City |
| Est. Birth Year | ~1918 |
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.
5 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Mary Harper | Daughter | — | 22 | ~1918 |
| Cecil Harper | Head | — | 50 | ~1890 |
| Doris Harper | Other | — | 20 | ~1920 |
| Lawrence Harper | Son | — | 26 | ~1914 |
| Minnie Harper | Spouse | — | 46 | ~1894 |
Census Appearances
1920
Rock Island, …
Daughter, age 2
Rock Island, Illinois · implied b. ~1918 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Harper |
| Given Name | Mary C. |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 2 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Iowa |
| Mother's Birthplace | Illinois |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1930
Rock Island, …
Daughter, age 12
Rock Island, Illinois · implied b. ~1918 — 5 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Harper |
| Given Name | Mary Katherine |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 12 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Iowa |
| Mother's Birthplace | Illinois |
| Can Read/Write | Yes |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Rock-Island-County, Illinois
Daughter, age 22
Rock-Island-County, Illinois · implied b. ~1918 — 5 household members
| Surname | Harper |
| Given Name | Mary Kathryn |
| Relationship to Head | Daughter |
| Sex | F |
| Color / Race | White |
| Age | 22 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Silvis City |
| 1935 Residence (County) | Rock Island |
| Occupation | Laborer |
| Industry | Rubber Shoe Co |
| Class of Worker | PW |
| Hours Worked | 4 |
| Income (1939) | 765 |
| Highest Grade | Hs 4 |
| 1935 Residence | Same place |
| 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 Mary Harper across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father Cecil Harper (~0.92 confidence) and mother Minnie Harper (~0.92 confidence) and mother Minnie Harper (~0.92 confidence). The pedigree spans 1 generation with 3 identified ancestors.
Show:
Gen 1
Parents
confidence ≈ 0.92
Father
Cecil Harper
b. ~1888
Source father
● Household
· direct · ~0.92
Mother
Minnie Harper
b. ~1894
Source mother
● Household
· direct · ~0.92
Mother
Minnie Harper
b. ~1894
Source mother
● Household
· direct · ~0.92
This person
Anchor record
Mary Harper
Daughter · 1940 · age 22 · b. ~1918 · Illinois
★ You are viewing this record
Sibling
Lawrence Harper
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 — Rock-Island-County, Illinois
Open full size
1940 US Federal Census — Rock-Island-County, Illinois
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-00874-00743)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | George Suss | 56 | Head | Traveling Salesman | Iowa |
| 2 | Christine Suss | 54 | Wife | — | Denmark |
| 3 | Irving Suss | 27 | Son | Laborer | Illinois |
| 4 | Helen Suss | 24 | Daughter | Stenographer | Illinois |
| 5 | Kenneth Suss | 22 | Son | Timekeeper | Illinois |
| 6 | Charles Suss | 20 | Son | Office Clerk | Illinois |
| 7 | Margaret Suss | 17 | Daughter | — | Illinois |
| 8 | Eldon Mcclellan | 45 | Head | Wrecker Engineer | Iowa |
| 9 | Ruth Mcclellan | 44 | Wife | Auditor | Illinois |
| 10 | Irene Ruge | 68 | Mother-in-law | — | Illinois |
| 11 | W. G. Brownlee | 47 | Head | Proprietor | Illinois |
| 12 | Yvonne Brownlee | 38 | Wife | — | Belgium |
| 13 | Betty Jane Brownlee | 15 | Daughter | — | Illinois |
| 14 | Dorothy J. Brownlee | 14 | Daughter | — | Illinois |
| 15 | S. J. Joseph | 55 | Head | Conductor | Iowa |
| 16 | Renetta Joseph | 44 | Wife | — | Iowa |
| 17 | Mary Katherine Joseph | 19 | Daughter | Stenographer | Illinois |
| 18 | Morris M. May | 28 | Son | Truck Driver | Illinois |
| 19 | Maxine E. May | 23 | Daughter-in-law | — | Iowa |
| 20 | Robert J. May | 2 | Grandson | — | Illinois |
| 21 | Cecil C. Harper | 50 | Head | Conductor | Iowa |
| 22 | Minnie Harper | 46 | Wife | — | Illinois |
| 23 | Mary Kathryn Harper THIS PERSON | 22 | Daughter | Laborer | Illinois |
| 24 | Lawrence J. Harper | 26 | Son | Tool Grinder | Illinois |
| 25 | Doris Harper | 20 | Daughter-in-law | — | Illinois |
| 26 | John Wickley | 31 | Head | Foreman | Illinois |
| 27 | Leona Wickley | 30 | Wife | Sales Lady | Illinois |
| 28 | Sandra Wickley | 3 | Daughter | — | Illinois |
| 29 | Clara Ranson | 53 | Mother-in-law | — | Iowa |
| 30 | Charles H. Mason | 53 | Head | Switchman | Iowa |
| 31 | Pansie Mason | 51 | Wife | — | Arkansas |
| 32 | — | None | — | — | — |
| 33 | — | None | — | — | — |
| 34 | Robert R. Penquite | 44 | Head | Brakeman | Iowa |
| 35 | Eleanor Penquite | 35 | Wife | — | Iowa |
| 36 | Nora Ruf | 54 | Head | — | Missouri |
| 37 | Hazel Arnold | 21 | Lodger | Waitress | Iowa |
| 38 | Leonard Polka | 21 | Lodger | Clerk | Iowa |
| 39 | — | None | — | — | — |
| 40 | W. D. Holdefer | 60 | Head | Refrig. Service Inspector | Iowa |
Pedigree Summary
Mary + 1 sibling
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)