JC
John Cooper — 1940 US Census Record
Model Tree available1940 United States Federal Census · Baltimore-City-County, Maryland
Our Model Tree links this John Cooper across the 1920, 1930 and 1940 US Censuses in Baltimore-City-County, Maryland (XGBoost, ~Confirmed), with identified parents Henry — first a head (b.~1893), then head of a 4-person household.
Age 47
b. ~1893
Male
Head
Born: Maryland
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Baltimore-City-County, Maryland |
| Surname | Cooper |
| Given Name | John F. |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 47 |
| Marital Status | Married |
| Birthplace | Maryland |
| 1935 Residence (City) | Baltimore City |
| 1935 Residence (County) | Baltimore City |
| Additional Details | |
| Occupation | Machinist |
| Industry | Piston Ring Co |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 1200 |
| Highest Grade | No 7 |
| 1935 Residence | Same Place |
| Birth State | Maryland |
| Birth Country | United States |
| Birthplace (normalized) | maryland |
| Occupation | Machinist |
| Township / Ward | Baltimore City |
| Est. Birth Year | ~1893 |
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.
4 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| Irene Cooper | Daughter | — | 11 | ~1929 |
| John Cooper | Head | — | 47 | ~1893 |
| John Cooper | Son | — | 26 | ~1914 |
| Carolyn Cooper | Spouse | — | 42 | ~1898 |
Census Appearances
1920
Baltimore, Maryland
Son, age 25
Baltimore, Maryland · implied b. ~1895 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Cooper |
| Given Name | John J. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | Black |
| Age | 25 |
| Marital Status | Single |
| Birthplace | Maryland |
| Father's Birthplace | Maryland |
| Mother's Birthplace | Maryland |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Maryland |
| Birth Country | United States |
| Birthplace (normalized) | maryland |
1930
Baltimore, Maryland
Head, age 37
Baltimore, Maryland · implied b. ~1893 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Cooper |
| Given Name | John F |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 37 |
| Marital Status | Married |
| Birthplace | Maryland |
| Age at First Marriage | 20 |
| Father's Birthplace | Maryland |
| Mother's Birthplace | Maryland |
| Occupation | Foreman |
| Industry | American Piston |
| Class of Worker | W |
| Can Read/Write | Yes |
| Home Owned/Rented | O |
| Home Value / Rent | 5500 |
| Radio Set | R |
| Birth State | Maryland |
| Birth Country | United States |
| Birthplace (normalized) | maryland |
1940
Baltimore-City-County, Maryland
Head, age 47
Baltimore-City-County, Maryland · implied b. ~1893 — 4 household members
| Surname | Cooper |
| Given Name | John F. |
| Relationship to Head | Head |
| Sex | M |
| Color / Race | White |
| Age | 47 |
| Marital Status | Married |
| Birthplace | Maryland |
| 1935 Residence (City) | Baltimore City |
| 1935 Residence (County) | Baltimore City |
| Occupation | Machinist |
| Industry | Piston Ring Co |
| Class of Worker | PW |
| Hours Worked | 40 |
| Income (1939) | 1200 |
| Highest Grade | No 7 |
| 1935 Residence | Same Place |
| Birth State | Maryland |
| Birth Country | United States |
| Birthplace (normalized) | maryland |
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 Cooper across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage. Identified parents: father Henry Cooper (~0.80 confidence). The pedigree spans 1 generation with 1 identified ancestor.
Show:
Gen 1
Parents
confidence ≈ 0.8
Father
Henry Cooper
b. ~None
Source father
● Household
· direct · ~0.8
This person
Anchor record
John Cooper
Head · 1940 · age 47 · b. ~1893 · Maryland
★ You are viewing this record
Confirmed / household (~0.90+)
Probable / derived (~0.65–0.89)
Candidate (<0.65, unverified)
Original Census Page
1940 US Federal Census — Baltimore-City-County, Maryland
Open full size
1940 US Federal Census — Baltimore-City-County, Maryland
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01515-00359)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | John F. Cooper THIS PERSON | 47 | Head | Machinist | Maryland |
| 2 | Carolyn G. Cooper | 42 | Wife | — | Maryland |
| 3 | John T. Cooper | 26 | Son | Auditor | Maryland |
| 4 | Irene Cooper | 11 | Daughter | — | Maryland |
| 5 | James A. Holland | 47 | Head | Carpenter | Maryland |
| 6 | Catherine Holland | 45 | Wife | — | Maryland |
| 7 | Howard Holland | 22 | Son | Draftsman | Maryland |
| 8 | Robert Holland | 14 | Son | — | Maryland |
| 9 | Mary M. Donohue | 76 | Mother-in-law | — | Maryland |
| 10 | James H. G. Higgins | 67 | Head | — | Maryland |
| 11 | Helen R. Higgins | 64 | Wife | — | Maryland |
| 12 | Robert Lee | 65 | Brother-in-law | — | Maryland |
| 13 | Alton C. Linkous | 38 | Head | U.S. Ranger | Virginia |
| 14 | Lila Linkous | 36 | Wife | Saleslady | Georgia |
| 15 | Wesley Jr. Linkous | 15 | Daughter | — | Virginia |
| 16 | Alton Jr. Linkous | 10 | Son | — | Virginia |
| 17 | Ludwick Linkous | 8 | Son | — | Virginia |
| 18 | Delia Webb | 64 | Mother-in-law | — | Virginia |
| 19 | Carrie W. Wythe | 68 | Mother-in-law | — | Alabama |
| 20 | Howard Warneke | 55 | Head | Printer | Maryland |
| 21 | Elizabeth H. G. Warneke | 54 | Wife | — | Maryland |
| 22 | Catherine I. Warneke | 29 | Daughter | Stenographer | Maryland |
| 23 | Irvine Warneke | 25 | Son | Accountant | Maryland |
| 24 | Helen M. Warneke | 20 | Daughter | Stenographer | Maryland |
| 25 | Wesley P. Kellard | 46 | Head | Manager | Boston |
| 26 | Emma H. Kellard | 45 | Wife | — | Maryland |
| 27 | Richard T. Kellard | 20 | Son | — | Maryland |
| 28 | Robert P. Kellard | 13 | Son | — | Maryland |
| 29 | Mason J. Startt | 28 | Head | Operator Telephone | Maryland |
| 30 | Thelma E. Startt | 25 | Wife | Clerk Billing | Maryland |
| 31 | Henry Cooper | 28 | Head | Foreman | Maryland |
| 32 | Edna Cooper | 27 | Wife | — | Maryland |
| 33 | Martha Placht | 62 | Head | — | Germany |
| 34 | Edward J. Gannon | 59 | Head | — | Ireland |
| 35 | Alice Gannon | 59 | Wife | — | Ireland |
| 36 | John H. Schroll | 39 | Son-in-law | Splicer | Maryland |
| 37 | Alice T. Schroll | 32 | Daughter | — | Maryland |
| 38 | Howard Carter | 27 | Head | Electric Welder | Pennsylvania |
| 39 | Laura Carter | 27 | Wife | — | Maryland |
| 40 | Gene Cooper | 1 | Son | — | Maryland |
Pedigree Summary
John
Gen 1 · 1 parents
~0.8
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)