John Mcmahon — 1940 US Census Record

Linked across censuses

1940 United States Federal Census · Kings-County, New York

Our Model Tree links this John Mcmahon across the 1920, 1930 and 1940 US Censuses in Kings-County, New York (XGBoost, ~Confirmed) — first a head (b.~1870), then head of a 5-person household.

Age 70 b. ~1870 Male Head Born: Ireland Married

1940 Census Record Details

Census Year	1940
Location	Kings-County, New York
Surname	McMahon
Given Name	John
Relationship to Head	Head
Sex	M
Color / Race	White
Age	70
Marital Status	Married
Birthplace	Ireland
1935 Residence (City)	New York City
1935 Residence (County)	Kings
Naturalization Status	Naturalized
Additional Details
Occupation	Watchman
Industry	Docker
Class of Worker	PW
Hours Worked	48
Income (1939)	602
Highest Grade	No 4
1935 Residence	Same House
Birth Country	Ireland
Birthplace (normalized)	ireland
Occupation	Watchman
Township / Ward	New York City
Est. Birth Year	~1870

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 John	Age	Birth yr
Catherine Mcmahon	Daughter	—	38	~1902
Frances Mcmahon	Daughter	—	32	~1908
John Mcmahon	Head	—	70	~1870
Thomas Mcmahon	Son	—	40	~1900
Catherine Mcmahon	Spouse	—	70	~1870

Census Appearances

1920

Kings, New …

Head, age 46

Kings, New York · implied b. ~1874 — 3 household members

● Primary link · ~Confirmed · 2 sources

XGBoost Household

Surname	McMahon
Given Name	John J
Relationship to Head	Head
Sex	M
Color / Race	White
Age	46
Marital Status	Married
Birthplace	Ireland
Year of Immigration	1895
Naturalization Status	Naturalized
Father's Birthplace	Ireland
Mother's Birthplace	Ireland
Occupation	Janitor
Industry	Apartment
Class of Worker	W
Can Read	Yes
Can Write	Yes
Speaks English	Yes
Mother Tongue	Irish
Home Owned/Rented	R
Birth Country	Ireland
Year of Naturalization	1904
Birthplace (normalized)	ireland

1930

Kings, New …

Head, age 60

Kings, New York · implied b. ~1870 — 6 household members

● Primary link · ~Confirmed · 2 sources

XGBoost Household

Surname	McMahon
Given Name	John
Relationship to Head	Head
Sex	M
Color / Race	White
Age	60
Marital Status	Widowed
Birthplace	Ireland
Age at First Marriage	25
Father's Birthplace	Ireland
Mother's Birthplace	Ireland
Occupation	Helper
Industry	Coal Co.
Class of Worker	W
Can Read/Write	Yes
Mother Tongue	English
Birth Country	Ireland
Birthplace (normalized)	ireland

1940

Kings-County, New …

Head, age 70

Kings-County, New York · implied b. ~1870 — 5 household members

Surname	McMahon
Given Name	John
Relationship to Head	Head
Sex	M
Color / Race	White
Age	70
Marital Status	Married
Birthplace	Ireland
1935 Residence (City)	New York City
1935 Residence (County)	Kings
Naturalization Status	Naturalized
Occupation	Watchman
Industry	Docker
Class of Worker	PW
Hours Worked	48
Income (1939)	602
Highest Grade	No 4
1935 Residence	Same House
Birth Country	Ireland
Birthplace (normalized)	ireland

Model Tree

Linked across censuses

Our Model Tree links John Mcmahon across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage.

Show:

This person

Anchor record

John Mcmahon

Head · 1940 · age 70 · b. ~1870 · New York

★ 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 — Kings-County, New York Open full size

Page Contents

40 people indexed on this census page (nara:1940:m-t0627-02558-00747)

Line	Name	Age	Relation	Occupation	Birthplace
1	Edward Whalen	44	Roomer	Locksmith	New York
2	Louis Lahm	50	Roomer	Factory Work	Germany
3	John Roble	44	Roomer	—	New Jersey
4	Anna Ryan	63	Roomer	—	Ireland
5	Henry O'Neill	67	Head	Clerk	New York
6	Catherine O'Neill	64	Wife	—	New York
7	Catherine O'Neill	29	Daughter	Typist	New York
8	Marie O'Neill	22	Daughter	Receiving Clerk	New York
9	John Murphy	33	Head	Dept Manager	New York
10	Margaret Murphy	31	Wife	—	New York
11	Marie Murphy	4	Daughter	—	New York
12	Anne Murphy	2	Daughter	—	New York
13	Peter Grolio	32	Head	Plasterer	New York
14	Anna Grolio	26	Wife	—	Pennsylvania
15	Gerald Katchinski	8	Step-son	—	Pennsylvania
16	Anthony Castagna	44	Head	Mineral Water Business	New York
17	Helen Castagna	37	Wife	—	New York
18	Richard Castagna	9	Son	—	New York
19	William Meeghan	53	Head	Loader	New York
20	Florence Meeghan	51	Wife	—	New York
21	William Meeghan	25	Son	Loader	New York
22	John Meeghan	16	Son	Loader	New York
23	Grace Meeghan	22	Daughter	Labeler	New York
24	Dorothy Meeghan	20	Daughter	Envelope Operator	New York
25	Edwin Meeghan	15	Son	Order Boy	New York
26	Martha Meeghan	16	Daughter	—	New York
27	Gerard Meeghan	13	Son	—	New York
28	Mary Nelson	65	Head	—	Ireland
29	Nora Nelson	35	Daughter	Child Nutrition	New York
30	Ernest Nelson	33	Son	Clothing Bus	New York
31	John V. Bonk	54	Head	Account Clerk	New York
32	Ethel Bonk	45	Wife	—	New Jersey
33	Stasia Bonk	75	Mother-in-law	—	Germany
34	John Mcmahon THIS PERSON	70	Head	Watchman	Ireland
35	Catherine Mcmahon	70	Wife	—	Ireland
36	Thomas Mcmahon	40	Son	Electric Stat	New York
37	Catherine Mcmahon	38	Daughter	File Clerk	New York
38	Frances Mcmahon	32	Daughter	File Clerk	New York
39	Edward Talbot	46	Head	Clerk	New York
40	Marion Talbot	44	Wife	—	New York

Search for John Mcmahon

All John Mcmahon Census Records Discover Mcmahon Family Tree

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)

Report inaccurate data