Nancy Mulnix, born November 26, 1939 in Flint, Michigan, is the daughter of Robert G. Middlesworth, a General Motors executive, and his wife, Margaret. The family moved successively to Birmingham, Michigan, then Kansas City, Missouri, and then East Grand Rapids, Michigan. Nancy graduated from East Grand Rapids High School in 1957. She attended Drake University, Michigan State University and Aquinas College, from which she received her B.A. in Philosophy in 1978. In 1980 she received an M.A. degree in psychological counseling from the University of Notre Dame. In 1995, she received a Bachelors of Science in Nursing (Psychiatric) from Grand Valley State University.

Nancy Middlesworth married LeVant Mulnix III in 1959. The Mulnix family owned the Carpenter Paper Company in Grand Rapids, in which Lee Mulnix took an active role. The couple had four children: Robert, Kathryn, Michael, and later Susan, who is Korean by birth. The couple was divorced in 1977. In 1980 Nancy Mulnix moved to Chicago where she worked as a medical psychologist at the University of Illinois Medical Center’s Center for Craniofacial Anomalies. In 1982 she moved to Lantana, Florida to work as a counselor and bereavement coordinator at Hospice of Palm Beach County.

During her years in Grand Rapids, Nancy Mulnix has been involved in many organizations related to the arts. She was chairman of the Grand Valley State Colleges Foundation; chairman of several programs included in the Grand Rapids Arts Festivals; a member of the Grand Rapids Art Museum Education Committee; and served on the Michigan Council for the Arts from 1971 to 1975. She performed in “Tarradiddle Tales” and Tarradiddle Travels,” Grand Rapids Civic Theater productions of children’s plays. She also acted in the Civic Theatre’s productions of “Death of a Salesman,” “A Midsummer’s Night Dream,” and “Inspecting Carol.” A playbill autographed by her friend and author, Arthur Miller, is included in this collection.

Nancy Mulnix is perhaps best known for her leadership in the City of Grand Rapids acquisition of the Alexander Calder sculpture La Grande Vitesse, and Calder’s subsequent work Calder on the Roof. The bulk of this archival collection documents her initiation and participation in the Vandenberg Center Sculpture Project. Calder’s La Grande Vitesse is the first sculpture in the United States to be supported with public funds for the arts, under the National Endowment for the Arts.

Nancy's work on the project began in 1967 with a visit from Henry Geldzehler, then Associate Curator of American Painting and Sculpture at the Metropolitan Museum of Art. Geldzehler delivered a lecture in Grand Rapids, Apr. 7, 1967 to the women’s group of the Grand Rapids Art Museum, when Mulnix was serving as Vice President. Mulnix gave Geldzahler a tour, including a section of downtown Grand Rapids, Michigan, razed for urban renewal, where construction of the Vandenberg Center multi-building complex was about to begin. Geldzehler suggested the possibility of a work of public art for the space. Mulnix followed up on this idea on April 10, 1967, when she hand wrote a letter to Congressman Gerald R. Ford, of Grand Rapids, asking for his assistance in obtaining the grant funding. Ford pursued the funding on behalf of Grand Rapids, though he had been politically against the formation and funding of the National Endowment for the Arts. Mulnix sought the expertise and support of Judge Stuart Hoffius, and Grand Rapids Mayor Christian Sonnevelt to initiate the project. The architectural firm of Skidmore Owings and Merrill was quickly involved in the planning, bringing to the project William Hartmann, the SOM partner who had recently brought the Picasso sculpture to Chicago. Leading citizens were appointed by the Mayor to the Vandenberg Center Sculpture Committee, including Peter Wege as Co-Chair with Mulnix. A separate group of six local and national art experts was formed to decide upon the artist to create the sculpture for the plaza. Alexander Calder (1898-1976), America's preeminent sculptor, was selected. Mulnix met Alexander Calder for the first time at Dec. 1967 at Perls Gallery in New York City. They became close friends during the project, and continued visits and correspondence until Calder’s death in 1976.

In the Fall of 2005, Nancy Middlesworth Mulnix married R. Bruce Tweddale.