Biographical Database of NAWSA Suffragists, 1890-1920

Biography of Mary Peet Sleeper, 1868-

By Sam Reed, undergraduate student

Harvard University, Cambridge, MA

Mary P. Sleeper (born Mary Peet) was born in New Oregon, Iowa in 1868 to Stephen Denison Peet and Olive Cutler. She married Henry Dike Sleeper (1865-1948) on August 28th, 1894 in McDonough County, Illinois, and together they had three children: Mary Olive (1896-1954), Harriet (1902-1975), and William Denison (1904-1930). When Henry, who studied music at Harvard College, was offered a job to teach music at Smith, the family moved to Northampton, Massachusetts.

In the first few years of the 20th century, after moving to Massachusetts, Mary began to get involved in several regional social initiatives. The first was the Massachusetts Society for the Prevention of Cruelty to Children, to which Mary donated $2 (equivalent to approximately $50 today) in 1909. Not long after this, however, her attention was captured by the issue of women's suffrage. By 1914, she was President of the Northampton Equal Suffrage League, and on February 12th of that year, she gave a speech at the inaugural meeting of the Suffrage Discussion Club at Smith College. This activity in the Boston area caught the attention of the Massachusetts State branch of the Congressional Union (later known as the National Woman's Party), which she joined soon thereafter. In 1916, she assisted Mrs. Elizabeth Tilton in the formation of an advisory council to the Party, consisting of 100 influential men from around the state who showed interest in supporting their campaign to achieve women's suffrage. Not long after this, in 1919-1920, Mary Sleeper and Grace A Johnson collaborated on "A Citizen's Guide for the Boston Equal Suffrage Association for Good Government."

After approximately 20 years in Northampton, Mary and Henry began to look for a new location. In June of 1921, they purchased a camp on the shores of Lake Champlain, in Ferrisburg, Vermont. Due to Henry's job, they continued to spend the school year in Massachusetts, but their summers were now spent running "Camp Marbury," an all-girls summer camp so named for Massachusetts Bay Colony resident Anne Marbury Hutchinson (1591-1643), who was known as an early women's rights activist for breaking traditional gender roles of the time and giving sermons to those in her town. Camp Marbury, which hosted as many as 50 female campers and 25 staff at its peak, operated from 1921 until 1942 as a girls' camp, and, under Mary's supervision, continued on as a camp for 10-15 adults until 1945. In 1945, Mary auctioned off much of the camp equipment and real estate, leaving the rest of the property to her daughter, Harriet. Mary and Henry then moved to Winter Park, Florida, where they remained until Henry's death in 1948, after which she moved to Plainfield, New Jersey with her daughter Harriet and lived out the rest of her days.


Annual Report for the Massachusetts Society for the Prevention of Cruelty to Children. Rep. Boston: George H. Ellis, 1909. Web. 5 Mar. 2017.

"Cambridge Women's Heritage Project Database, J." Cambridge Women's Heritage Project Database, J. N.p., Mar. 2010. Web. 06 Mar. 2017.

Illinois Marriage Index, 1860-1920. 6 Mar. 2017. "News and Reviews from University and College." Oregon Daily Journal [Portland] 22 Feb. 1914: 8. Web.

"Obituaries." Winter Park Topics 6 Feb. 1948: n. pag. Print.

Page, Priscilla, comp. "Sleeper Family/Camp Marbury Papers." (2007): n. pag. Rpt. in Vermont Historical Society. N.p.: n.p., n.d. Web. 5 Mar. 2017.

United States Census, 1920. Accessed 5 Mar. 2017.

Stanton, Elizabeth Cady, Susan B. Anthony, Matilda Joslyn Gage, and Ida Husted Harper. History of Woman Suffrage. Vol. 6.

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