Jeannette Augustus Marks was born in Chattanooga, Tennessee on August 16, 1875. Her father, William Dennis Marks met and married her mother, Jeannette Colwell, while running a factory in Tennessee. He later went on to become professor of engineering at the University of Pennsylvania and president of the Philadelphia Edison Company. Jeannette Marks was educated at boarding schools in the United States and Europe and went on to attend Dana Hall and then Wellesley College where she received her B.A. in 1900. It was here that Marks met Mary Emma Woolley, then a Wellesley professor, who was to remain her companion for the next fifty years. Soon after her inauguration as president of Mount Holyoke, Woolley appointed Marks instructor in the English Department, which she would eventually chair. While at the college, Marks founded the Play and Poetry Shop Talks lecture series inviting notable authors and poets to Mount Holyoke to discuss modern literature. She also started the Laboratory Theatre in 1928, which would become her primary focus at the college until her retirement in 1941. Marks began writing short stories while a student at Wellesley and continued to publish throughout her career. Most notable among her writings were "The Family of the Barretts", a biography of the family of Elizabeth Barrett Browning, and "The Life and Letters of Mary Emma Woolley". She also conducted a great deal of research on narcotics and published several books pertaining to drug addiction. She was a member of the National Women's Party, the first organization to support the Equal Rights Amendment. Her political activities also included advocacy for Sacco and Vanzetti and Eugene V. Debs. While it is unclear if Marks identified herself as a socialist, she corresponded with and donated money to local and national socialist causes throughout the 1920s. After her retirement in 1941, she moved permanently to her childhood home, Fleur De Lys, on Lake Champlain in New York with Mary Woolley. Marks died on March 15, 1964 in Westport, New York at the age of 88.