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James Donnelly — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Buchanan-County, Iowa
Our Model Tree links this James Donnelly across the 1930 and 1940 US Censuses in Buchanan-County, Iowa (XGBoost, ~Confirmed) — first a son (b.~1925), then head of a 7-person household.
Age 15
b. ~1925
Male
Son
Born: Iowa
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Buchanan-County, Iowa |
| Surname | Donnelly |
| Given Name | James T. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 15 |
| Marital Status | Single |
| Birthplace | Iowa |
| 1935 Residence (City) | Washington Twp. |
| Additional Details | |
| Highest Grade | H 1 |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
| Township / Ward | Washington Twp |
| Est. Birth Year | ~1925 |
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 |
|---|---|---|---|---|
| James Donnelly | Son | — | 15 | ~1925 |
| Bernard Donnelly | Head | — | 48 | ~1892 |
| Floyd Donnelly | Son | — | 16 | ~1924 |
| John Donnelly | Son | — | 19 | ~1921 |
| Josie Donnelly | Spouse | — | 48 | ~1892 |
| Leonard Donnelly | Son | — | 23 | ~1917 |
| William Donnelly | Son | — | 13 | ~1927 |
Census Appearances
1930
Buchanan, Iowa
Son, age 5
Buchanan, Iowa · implied b. ~1925 — 14 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Donnelly |
| Given Name | James |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 5 |
| Marital Status | Single |
| Birthplace | Iowa |
| Father's Birthplace | Iowa |
| Mother's Birthplace | Iowa |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
1940
Buchanan-County, Iowa
Son, age 15
Buchanan-County, Iowa · implied b. ~1925 — 7 household members
| Surname | Donnelly |
| Given Name | James T. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 15 |
| Marital Status | Single |
| Birthplace | Iowa |
| 1935 Residence (City) | Washington Twp. |
| Highest Grade | H 1 |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
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 Donnelly across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
James Donnelly
Son · 1940 · age 15 · b. ~1925 · Iowa
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Sibling
Leonard Donnelly
Sibling · 1940 · age 23
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Floyd Donnelly
Sibling · 1940 · age 16
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
William Donnelly
Sibling · 1940 · age 13
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
John Donnelly
Sibling · 1940 · age 19
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 — Buchanan-County, Iowa
Open full size
1940 US Federal Census — Buchanan-County, Iowa
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01142-01088)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Boyd A. Williamson | 7 | Son | — | Iowa |
| 42 | Robert C. Williamson | 3 | Son | — | Iowa |
| 43 | Bert P. Swanson | 40 | Head | Carpenter | Iowa |
| 44 | June B. Swanson | 26 | Wife | — | Iowa |
| 45 | Eugene A. Swanson | 5 | Son | — | Iowa |
| 46 | Joy G. Swanson | 3 | Daughter | — | Iowa |
| 47 | Harry D. Swanson | 1 | Son | — | Iowa |
| 48 | John Johnson | 49 | Head | Farming | Norway |
| 49 | Sina T. Johnson | 43 | Wife | — | Norway |
| 50 | George A. Johnson | 22 | Son | Laborer | S. Dakota |
| 51 | Susan J. Johnson | 13 | Daughter | — | S. Dakota |
| 52 | John R. Johnson | 10 | Son | — | S. Dakota |
| 53 | Wade E. Crawford | 54 | Head | Farming | Illinois |
| 54 | Louise E. Crawford | 49 | Wife | — | Iowa |
| 55 | Wylma M. Crawford | 22 | Daughter | Housework | Iowa |
| 56 | Norine K. Crawford | 20 | Daughter | — | Iowa |
| 57 | Ceryl A. Crawford | 18 | Son | Laborer | Iowa |
| 58 | Carl W. Crawford | 16 | Son | — | Iowa |
| 59 | Donald D. Crawford | 9 | Son | — | Iowa |
| 60 | Robert W. Crawford | 14 | Son | — | Iowa |
| 61 | Donna D. Crawford | 13 | Daughter | — | Iowa |
| 62 | Bernard Donnelly | 48 | Head | Farming | Iowa |
| 63 | Josie E. Donnelly | 48 | Wife | — | Iowa |
| 64 | Leonard A. Donnelly | 23 | Son | Farm Trucking | Iowa |
| 65 | John P. Donnelly | 19 | Son | — | Iowa |
| 66 | Floyd Donnelly | 16 | Son | — | Iowa |
| 67 | James T. Donnelly THIS PERSON | 15 | Son | — | Iowa |
| 68 | William B. Donnelly | 13 | Son | — | Iowa |
| 69 | William Armstrong | 26 | Head | Farming | Iowa |
| 70 | Gertrude D. Armstrong | 21 | Wife | — | Illinois |
| 71 | John P. Leonard | 54 | Head | Farming | Iowa |
| 72 | Mary J. Leonard | 50 | Wife | — | Iowa |
| 73 | Rita A. Leonard | 12 | Daughter | — | S. Dakota |
| 74 | Patricia E. Leonard | 7 | Daughter | — | S. Dakota |
| 75 | Guy Butler | 50 | Hired Hand | Farming | Iowa |
| 76 | George P. Fissel | 74 | Head | — | Iowa |
| 77 | Rebeka A. Fissel | 70 | Wife | — | Wisconsin |
| 78 | Harry J. Brannon | 51 | Head | Farming | Iowa |
| 79 | Josie B. Brannon | 50 | Wife | — | Iowa |
| 80 | Lucille J. Brannon | 15 | Daughter | — | Iowa |
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)