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Mary Williamson — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Boulder-County, Colorado
Our Model Tree links this Mary Williamson across the 1920, 1930 and 1940 US Censuses in Boulder-County, Colorado (XGBoost, ~Confirmed) — first a spouse (b.~1888), then head of a 4-person household.
Age 52
b. ~1888
Female
Spouse
Born: Colorado
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | Boulder-County, Colorado |
| Surname | Williamson |
| Given Name | Mary E. |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 52 |
| Marital Status | Married |
| Birthplace | Colorado |
| 1935 Residence (City) | Longmont City |
| 1935 Residence (County) | Boulder |
| Additional Details | |
| Income (1939) | 0 |
| Highest Grade | Hs 4 |
| 1935 Residence | Same house |
| Birth State | Colorado |
| Birth Country | United States |
| Birthplace (normalized) | colorado |
| Township / Ward | Longmont City |
| Est. Birth Year | ~1888 |
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 Mary | Age | Birth yr |
|---|---|---|---|---|
| Alice Williamson | Daughter | — | 21 | ~1919 |
| Joseph Williamson | Head | — | 54 | ~1886 |
| James Williamson | Son | — | 25 | ~1915 |
| Mary Williamson | Spouse | — | 52 | ~1888 |
Census Appearances
1920
Boulder, Colorado
Spouse, age 31
Boulder, Colorado · implied b. ~1889 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Williamson |
| Given Name | Mary |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 31 |
| Marital Status | Married |
| Birthplace | Colorado |
| Father's Birthplace | Canada English |
| Mother's Birthplace | Canada |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Birth State | Colorado |
| Birth Country | United States |
| Birthplace (normalized) | colorado |
1930
Boulder, Colorado
Spouse, age 42
Boulder, Colorado · implied b. ~1888 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Williamson |
| Given Name | Mary C |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 42 |
| Marital Status | Married |
| Birthplace | Colorado |
| Age at First Marriage | 21 |
| Father's Birthplace | Canada English |
| Mother's Birthplace | Canada English |
| Can Read/Write | Yes |
| Birth State | Colorado |
| Birth Country | United States |
| Birthplace (normalized) | colorado |
1940
Boulder-County, Colorado
Spouse, age 52
Boulder-County, Colorado · implied b. ~1888 — 4 household members
| Surname | Williamson |
| Given Name | Mary E. |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 52 |
| Marital Status | Married |
| Birthplace | Colorado |
| 1935 Residence (City) | Longmont City |
| 1935 Residence (County) | Boulder |
| Income (1939) | 0 |
| Highest Grade | Hs 4 |
| 1935 Residence | Same house |
| Birth State | Colorado |
| Birth Country | United States |
| Birthplace (normalized) | colorado |
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 Williamson across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage.
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This person
Anchor record
Mary Williamson
Spouse · 1940 · age 52 · b. ~1888 · Colorado
★ 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 — Boulder-County, Colorado
Open full size
1940 US Federal Census — Boulder-County, Colorado
Page Contents
39 people indexed on this census page (nara:1940:m-t0627-00457-01061)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 1 | Marlene L. Nesmith | 1 | Daughter | — | Colorado |
| 2 | Clarence J. Nesmith | 46 | Head | Machinist | Kansas |
| 3 | Julia C. Nesmith | 46 | Wife | — | Texas |
| 4 | Mary Dolores Nesmith | 11 | Daughter | — | Colorado |
| 5 | Judy C. Van Patten | 19 | Niece | — | Colorado |
| 6 | Carl D. Lewis | 38 | Head | Furniture Dealer | Missouri |
| 7 | Stella C. Lewis | 38 | Wife | — | Iowa |
| 8 | Helen E. Lewis | 15 | Daughter | — | Colorado |
| 9 | K. Stanton Lewis | 11 | Son | — | Colorado |
| 10 | Robert T. Lewis | 3 | Son | — | Colorado |
| 11 | Edward W. Brown | 45 | Head | Janitor | Indiana |
| 12 | Dessa R. Brown | 47 | Wife | — | Indiana |
| 13 | Miriam R. Brown | 13 | Daughter | — | Colorado |
| 14 | Lillian C. Willson | 44 | Head | Secretary | Missouri |
| 15 | R. Jean Willson | 17 | Daughter | — | Colorado |
| 16 | Marian O. Willson | 65 | Mother-in-law | — | Iowa |
| 17 | Cora B. Flanders | 68 | Head | — | Minnesota |
| 18 | Laura A. Wood | 70 | Sister-in-law | — | New York |
| 20 | C. Oscar Almquist | 67 | Head | Salesman | Sweden |
| 21 | Emily Almquist | 59 | Wife | — | Colorado |
| 22 | Walter H. Hogsett | 55 | Head | Implement And Lumber Merchant | Illinois |
| 23 | Elsie C. Hogsett | 51 | Wife | — | Illinois |
| 24 | Glade C. Hogsett | 24 | Son | House Manager | Colorado |
| 25 | Samuel P. Whitehouse | 22 | Nephew | Dishwasher | Montana |
| 26 | Joseph D. Williamson | 54 | Head | Assistant Cashier | Kansas |
| 27 | Mary E. Williamson THIS PERSON | 52 | Wife | — | Colorado |
| 28 | James O. Williamson | 25 | Son | Bank Teller | Colorado |
| 29 | Alice Jean Williamson | 21 | Daughter | — | Colorado |
| 30 | Ray V. Kanyon | 57 | Head | Manager And Editor Newspaper | Colorado |
| 31 | Elsie M. Kanyon | 54 | Wife | — | Kansas |
| 32 | Joseph D. Mulligan | 55 | Head | Plumber | Colorado |
| 33 | Alice W. Mulligan | 50 | Wife | — | Illinois |
| 34 | William B. Slater | 55 | Head | — | New Jersey |
| 35 | Ethel B. Slater | 54 | Wife | — | Colorado |
| 36 | Ralph N. Oviatt | 73 | Head | — | Ohio |
| 37 | Edward W. Oviatt | 44 | Son | Civil Engineer | Colorado |
| 38 | Margaret A. Oviatt | 44 | Daughter-in-law | — | Kansas |
| 39 | Ralph H. Oviatt | 14 | Grandson | — | Missouri |
| 40 | John S. Smith | 40 | Head | Druggist | Oklahoma |
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)