Mary Withers Roper, school teacher, activist, committee member, missionary, and suffragist, was born to Benjamin Eliscus Roper and Catherine Withers Payne, both of Virginia, on October 22, 1857, in Lynchburg, Texas. The 1860 United States census recorded the family in Lynchburg, and her father was listed as a magistrate. Not much is documented about her life until the 1880s. According to the 1880 census, Mary Withers Roper, age twenty-two, was a public school teacher living in Houston, Texas. In 1888 she taught seventh grade at the Clopper Institute in Galveston, and she moved to Houston to teach seventh grade by 1897. In 1903 she traveled to the mountain resort town of Cloudcroft, New Mexico, to assist in opening a summer school for young girls from East Texas for the social season. Roper joined the Board of Missions in 1907 to work as a missionary teacher. On February 22, she left Houston for Tacuba, Mexico, where she taught at the Mary Josephine Hooker Memorial School. Roper later became assistant to the director of the Hooker School and Orphanage and the director of the Girls' Friendly Society in Popotla, Mexico City.
Roper's documented reform work as part of the woman suffrage movement began in 1903. The Texas Woman Suffrage Association held its first state convention on December 8, 1903, in Houston, where Roper was appointed to the Resolutions Committee. Their objective was to organize a state association to become part of the national organization of suffragists as well as to adopt and amend a constitution.
In addition to having an active role in the Texas Woman Suffrage Association and Texas Federation of Women’s Clubs, Roper was involved in many other causes. She was elected first vice president and chosen delegate to the fourth district convention to represent the Woman's Club of Houston in 1913. She presided over meetings of the Women's Political Union of Houston. She also assisted in organizing programs and entertainment at many club meetings and read original magazine articles and papers on women artists of the time for the Woman’s Club of Houston.
In October 1914 Roper became involved in the Houston Housewives League, which aimed to involve both single and married women in the community and help them to better manage their households. In June 1915 she represented the executive board of the fourth district of the Texas Federation of Women's Clubs for The Houston Post Good Roads car party on the Palestine campaign—the goal of which was to campaign for a highway between the cities of Palestine and Houston. She also served as part of the Committee on Resolutions in 1915, the Field Committee on Endowment in 1916, and chairman for the Fourth District State Endowment fund in 1916—all for the Texas Women’s Federation.
Not all of her philanthropic endeavors were club-related. Presumably for home front support of World War I, in 1918 Roper was a speaker at a Red Cross drive asking for aid and provisions in the form of bandages, clothing, food, medication, and money. By the 1930 census, she was retired from teaching and living at the Cotton Hotel in Houston. A member of Christ Episcopal Church, she never married. She remained in Houston until her death at the age of eighty-three on September 17, 1941. She was buried in Cedar Bayou Masonic Cemetery in Baytown and be-queathed the remainder of her estate, in excess of $11,000, to the Rice Institute, later named Rice University. Her donation was a memorial to her mother, Catherine Withers Roper, and father, Benjamin E. Roper, who were “pioneering contemporaries” of the founder of the institution. It was designated as a permanent endowment, beginning in the 1943–44 academic year. The memorial fund scholarship was still available until at least 2003.