JM
James Mckay — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Cook-County, Illinois
Our Model Tree links this James Mckay across the 1930 and 1940 US Censuses in Cook-County, Illinois (XGBoost, ~Confirmed) — first a son (b.~1929), then head of a 7-person household.
Age 11
b. ~1929
Male
Son
Born: Illinois
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Cook-County, Illinois |
| Surname | McKay |
| Given Name | James |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 11 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Additional Details | |
| Highest Grade | 4 |
| 1935 Residence | Same place |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
| Township / Ward | Chicago City |
| Est. Birth Year | ~1929 |
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.
7 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to James | Age | Birth yr |
|---|---|---|---|---|
| Mary Mckay | Spouse | — | 39 | ~1901 |
| Marietta Mckay | Daughter | — | 5 | ~1935 |
| John Mckay | Son | — | 14 | ~1926 |
| James Mckay | Son | — | 11 | ~1929 |
| Michael Mckay | Head | — | 43 | ~1897 |
| Daniel Mckay | Son | — | 7 | ~1933 |
| Michael Mckay | Son | — | 12 | ~1928 |
Census Appearances
1930
Cook, Illinois
Son, age 1
Cook, Illinois · implied b. ~1929 — 3 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Mackey |
| Given Name | James |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 1 |
| Marital Status | Single |
| Birthplace | Illinois |
| Father's Birthplace | Scotland |
| Mother's Birthplace | Scotland |
| Birth State | Illinois |
| Birth Country | United States |
| Birthplace (normalized) | illinois |
1940
Cook-County, Illinois
Son, age 11
Cook-County, Illinois · implied b. ~1929 — 7 household members
| Surname | McKay |
| Given Name | James |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 11 |
| Marital Status | Single |
| Birthplace | Illinois |
| 1935 Residence (City) | Chicago City |
| 1935 Residence (County) | Cook |
| Highest Grade | 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 James Mckay across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
James Mckay
Son · 1940 · age 11 · b. ~1929 · Illinois
★ You are viewing this record
Sibling
Marietta Mckay
Sibling · 1940 · age 5
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Daniel Mckay
Sibling · 1940 · age 7
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Michael Mckay
Sibling · 1940 · age 12
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
John Mckay
Sibling · 1940 · age 14
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 — Cook-County, Illinois
Open full size
1940 US Federal Census — Cook-County, Illinois
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01023-00174)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Elizabeth Miller | 14 | Daughter | — | Illinois |
| 2 | Louis Olson | 45 | Head | Printer | Norway |
| 3 | Mary Olson | 43 | Wife | Saleslady | Norway |
| 4 | Axel Lidman | 47 | Head | Lawyer | Illinois |
| 5 | Alberta Lidman | 39 | Wife | — | Wisconsin |
| 6 | Marjorie Lidman | 13 | Daughter | — | Illinois |
| 7 | James Lidman | 9 | Son | — | Illinois |
| 8 | Malene Grenholt | 48 | Sister-in-law | Milliner | Wisconsin |
| 9 | Peter Janisch | 60 | Head | Engineer | Wisconsin |
| 10 | Ellen Janisch | 58 | Wife | — | Sweden |
| 11 | Edward Janisch | 34 | Son | Bookkeeper | Illinois |
| 12 | Victor Swenson | 60 | Head | Bartender | Sweden |
| 13 | Donald Harold | 40 | Son-in-law | Credit Man | Illinois |
| 14 | Mildred Harold | 37 | Daughter | Bookkeeper | Illinois |
| 15 | Gust Erickson | 72 | Head | — | Sweden |
| 16 | Marion Erickson | 67 | Wife | — | Sweden |
| 17 | Richard Erickson | 49 | Son | Shipping Clerk | Illinois |
| 18 | Jenny Erickson | 47 | Daughter | Genl Office | Illinois |
| 19 | Fred Johnson | 54 | Head | Woodworker | Sweden |
| 20 | Alma Johnson | 51 | Wife | — | Sweden |
| 21 | Florence Johnson | 28 | Daughter | Genl Office | Illinois |
| 22 | Glen Johnson | 24 | Son | Genl Office | Illinois |
| 23 | Helen Johnson | 22 | Daughter | Bookkeeper | Illinois |
| 24 | Algot Johnson | 44 | Head | Pattern Maker | Sweden |
| 25 | Mildred Johnson | 44 | Wife | — | Illinois |
| 26 | Extra Line | None | — | — | — |
| 27 | Martin Dungen | 43 | Head | Conductor | Irish Free State |
| 28 | Alice Dungen | 33 | Wife | — | Minnesota |
| 29 | Mary Dungen | 9 | Daughter | — | Wisconsin |
| 30 | Theresa Dungen | 6 | Daughter | — | Illinois |
| 31 | Alice Dungen | 1 | Daughter | — | Illinois |
| 32 | Michael Mckay | 43 | Head | Proprietor | North Ireland |
| 33 | Mary Mckay | 39 | Wife | — | North Ireland |
| 34 | John Mckay | 14 | Son | — | Illinois |
| 35 | Michael Mckay | 12 | Son | — | Illinois |
| 36 | James Mckay THIS PERSON | 11 | Son | — | Illinois |
| 37 | Daniel Mckay | 7 | Son | — | Illinois |
| 38 | Marietta Mckay | 5 | Daughter | — | Illinois |
| 39 | Joseph Holmquist | 51 | Head | Supervisor Of Equipment | Illinois |
| 40 | Hilda Holmquist | 52 | Wife | — | Illinois |
Related Census Records
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)