About Mary Sibbet Copley
Lived 1843 – 1929 (aged 85). Mary Sibbet Copley was an American philanthropist.
Mary Sibbet Copley Thaw (June 19, 1843 – June 9, 1929) was an American philanthropist and charity worker.
Early life
Mary was born at Appleby Manor near Kittanning, Pennsylvania in Armstrong County on June 19, 1843. She was the daughter of Margaret and Josiah Copley, a pioneer editor who was well known in the community.
Personal life In 1867, she married William Thaw, Sr. (1818–1889) after the death of his first wife. Together, they had five children that survived childhood:
Harry Kendall Thaw (1871–1947), who would later murder Stanford White In his will, he left $10,000, less than 1% of his fortune, to wife Evelyn Nesbit. Edward Thaw (1873–1924), who married Jane Olmsted (1880–1958) Josiah Copley Thaw (1874–1944), who married Mary Harrington Thomson (1881–1947) Margaret Copley Thaw (1877–1942), who first married George Lauder Carnegie (1876–1921), nephew of Andrew Carnegie. After his death, she married Roger, Comte de Périgny and became Countess de Périgny. Alice Cornelia Thaw (1880–1955), who married George Seymour, 7th Marquess of Hertford (1871–1940). They divorced and she married Geoffrey George Whitney, Sr. in 1913.
She died, a few days before her 87th birthday, on June 9, 1929, of pneumonia. She was buried in Allegheny Cemetery in Pittsburgh.
Philanthropy After her husband's death in 1889, she used the wealth she inherited to fund archaeology research, including funds for prominent women archaeologists including Alice Fletcher and Zelia Nuttall. Thaw also funded the Thaw Fellowship at the Peabody Museum of Archaeology and Ethnology at Harvard College.
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Important facts
Family & relationships
People in Mary Sibbet Copley's life
Named in this biography and alive at the same time
Contemporaries
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Frequently asked questions
Who was Mary Sibbet Copley?
American philanthropist and charity worker
When was Mary Sibbet Copley born?
Mary Sibbet Copley was born on 19 June 1843 in Armstrong County.
When did Mary Sibbet Copley die?
Mary Sibbet Copley died on 6 June 1929 in Pittsburgh.
What was Mary Sibbet Copley's occupation?
Mary Sibbet Copley was a philanthropist.
What nationality was Mary Sibbet Copley?
Mary Sibbet Copley was American.
Sources & further reading
· Wikipedia: Mary Sibbet Copley
Cite this page
APA: Biography.guide. (2026). Mary Sibbet Copley. https://biography.guide/mary-sibbet-copley/
MLA: "Mary Sibbet Copley." Biography.guide, https://biography.guide/mary-sibbet-copley/.
Chicago: "Mary Sibbet Copley." Biography.guide. https://biography.guide/mary-sibbet-copley/.
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