Who were Mary (Foster) Thompson's parents?

Mary Foster married Thomas Thompson at Roxbury in 1765, and they settled at Thompson's Cove on Deer Isle, Maine. Their daughter Rebecca married Major Nathan Low, grandfather of Harriet (Low) Holbrook. Mollie's typescript makes Mary a daughter of John Foster of Roxbury and his wife Jane, and builds a long Boston ancestry above them: Foster, Kneeland, Payson, Bate, Bigg, Briscoe and Hawkins, with Capt. Hopestill Foster of Dorchester and Jane Hawkins, banished as an associate of Anne Hutchinson, among them. That whole branch rests on this one link, and no record found so far names Mary's parents.

Trail

1 Oct 2026: Mary's marriage and her age

The Roxbury records have "Foster ... Mary, and Thomas Thompson, Oct. 28, 1765" (2:153, and 2:394 under Thompson; Vital Records of Roxbury, Massachusetts, to the End of the Year 1849), so she married at Roxbury, not "in Boston or Dorchester" as Mollie has it. Hosmer's history of Deer Isle (1886) gives "1836, Mrs. Thompson, widow of Thomas Thompson, aged 91" (p. 218), so she was born about 1744/5. He also says Thomas Thompson's wife "was the sister of Mr. William Foster" (p. 47), the Deer Isle blacksmith who came from Dedham (p. 51) (Hosmer, An Historical Sketch of the Town of Deer Isle, Maine (1886)). A brother named William is the best clue to her family.

1 Oct 2026: Mollie's parents for her

Mollie makes Mary a daughter of John Foster (1722-1760) and his wife Jane (p. 114), and lists their children as Jane, John, Martha, William and Mary (Mollie Frances (Holbrook) Pfeiffer, Holbrook-Low family typescript, Books 1-9). She also repeats a story that Mary was "half French and Indian" (p. 119), which she rejects herself. Nothing supports the story: everything found places Mary among English Congregational families at Roxbury.

1 Oct 2026: John and Jane married in 1750

John Foster married Jane Lindsey at Boston on 20 Apr 1750, the intention entered on 9 Apr as "Jane Linsey" (Boston Record Commissioners 28:287, 344, image checked; Boston Record Commissioners, Reports (births, marriages and town records)). Their children were recorded at Roxbury: Samuel, 9 May 1751; William, 7 Feb 1753; Jane, 25 Mar 1755; and Martha, 21 Apr 1760, entered as "d. John [deceased July 6. C. R. 1.], and Jane" (1:134-135; Vital Records of Roxbury, Massachusetts, to the End of the Year 1849). Mary, born about five years before the marriage, cannot be a child of it, and there is no Mary among the Roxbury births.

1 Oct 2026: John's estate, known only from the index

The Suffolk probate index has an administration on John Foster's estate in 1760 (no. 12403) and guardianships in 1773 for his children John (15400), Martha (15401) and Jane (15599) (Index to the Probate Records of the County of Suffolk, Massachusetts). No Mary is among them. Mollie cites a division of the estate as "Lib. 73, fol. 14." None of these files has been read. If Mary was John's daughter by an earlier wife, the division is the record most likely to name her. (Inference: in 1773 Mary was about 28 and eight years married, so she would not have had a guardian, and her absence from the guardianships tells little either way.)

1 Oct 2026: William Foster of Deer Isle

A William Foster married Mary Draper of Dedham at Roxbury on 11 June 1778 (Vital Records of Roxbury, Massachusetts, to the End of the Year 1849). Mollie takes him to be John and Jane's son William, born 1753, and he is taken to be Hosmer's William Foster of Deer Isle, who came from Dedham and was Mrs. Thompson's brother. The marriage is documented; that these Williams are one man is an inference. If they are, and Mary was John's daughter by an earlier wife, she was William's half-sister, which still fits Hosmer's word "sister."

1 Oct 2026: Other candidates checked

No marriage of a John Foster in 1743-46 was found at Boston or Roxbury, and a Boston intention of John Foster and Elizabeth Woods, 14 Nov 1747, is too late. A Mary, daughter of Thomas and Mary Foster, was born at Dorchester on 2 Feb 1741/2, but she would have been 94 in 1836, not 91. No earlier wife of John Foster, and no other good candidate for Mary, has turned up.

1 Oct 2026: The generation above John

That John was born in 1722, son of Samuel Foster, periwig-maker, and Rachel Kneeland, rests only on Pierce's Foster Genealogy (1899), p. 539: "JOHN, b. in 1722; m. Jane" (Pierce, Foster Genealogy (1899)). No birth or baptism was found. The Suffolk index has a Samuel Foster will of 1728 (no. 5650) that may be his father's. So even if Mary is John's daughter, the next step up is compiled, not documented.

2 Oct 2026: Left as a research task

On review of the open conflicts, the ruling was that Mary's father is unknown: the link stays as recorded, with John Foster as possible, and it is a research task, not a decision (research/decisions.md).

6 Oct 2026: The Deer Isle families typescript

The Low master research read a typescript of Deer Isle family records on FamilySearch (Genealogical history of Deer Isle families (typescript)). Its Thompson pages give Thomas and Mary's children with Deer Isle birth dates, Rebecca among them on 12 May 1772; a Roxbury baptism of a son Thomas on 11 Jan 1767 (First Religious Society); and, from the town records, "Widow Mary Thompson Deceased March -- 1837," against Hosmer's 1836. With the Boxford marriage of "Nathan, jr., and Rebecca Thompson of Dear Isle," 23 Oct 1792 (Vital Records of Boxford, Massachusetts, to the End of the Year 1849), and Nathan Low's deed of 1803, bounded by Thomas Thompson's land (Deed of Nathan Low of Deer Isle, gentleman, to Ignatius Haskell, land on Eggemoggin Reach), Rebecca's place as Thomas and Mary's daughter is rated probable. Nothing in the typescript bears on Mary's own parents, and the master research leaves her father "Possible (unchanged)."

13 Oct 2026: Her death from the town record

Of the two dates for Mary's death, the town record's, March 1837, is taken over Hosmer's 1836, written fifty years later; Hosmer's "aged 91" still puts her birth about 1745 (the ruling of 13 Oct 2026, research/decisions.md).

Where it stands

Mary (Foster) Thompson's parents are not proved. The archive records John Foster (b. 1722?, d. by 6 July 1760) as her father, inferred and possible only, and records no mother. John and Jane cannot both be her parents, since they married when she was about five; she may be John's daughter by an earlier, unidentified wife, or belong to another Foster family altogether. Her marriage to Thomas Thompson is proven and Rebecca's descent from them probable. She died at Deer Isle in March 1837, as the town record has it, and her birth about 1745 rests on her age at death. John's own parents, Samuel Foster and Rachel Kneeland, are possible, on Pierce alone. Until a record names Mary's parents, the Foster, Kneeland, Payson, Bate, Bigg, Briscoe and Hawkins ancestry above her is provisional.

Next

• Suffolk Probate no. 12403 (John Foster, administration 1760), with the division Mollie cites as "Lib. 73, fol. 14," and the 1773 guardianships nos. 15400, 15401 and 15599 (FamilySearch, Suffolk County probate images; free). A division naming Mary Thompson, or Thomas Thompson in her right, among the heirs would prove her John's daughter. Mollie's list of John's children leaves out Samuel and includes a John who is not among the Roxbury births but had a guardian in 1773; whether she took it from this division is not known.
• Mary's baptism, about 1745 (the Roxbury First Church's own records; free where online). A baptism would name her father. The printed Roxbury vital records, drawn from the town and church records, have no Mary. The same books may also confirm her son Thomas's baptism of 11 Jan 1767, known so far only from the Deer Isle typescript.
• A first marriage of John Foster, about 1743-45 (Massachusetts town records beyond Boston and Roxbury, which have been searched; free where online). It would name Mary's mother if she was John's daughter by an earlier wife.
• Samuel Foster's will of 1728 (Suffolk Probate no. 5650; FamilySearch; free). If it is the periwig-maker's and names a son John, it documents the step above John, which now rests on Pierce alone.
• Mary's gravestone and her death entry in the Deer Isle town books (Deer Isle; the town books are filmed by FamilySearch; free). Her age at death, 91 in Hosmer, is the only evidence for her birth year; the town's entry, known so far as the typescript quotes it, should be seen whole.