Born in 1900 in the small town of Lyons, Georgia, Winthrop-King came to Tallahassee in 1928 to teach Spanish and French at Florida State College for Women. She taught at two different times until 1938. After earning a master's degree at Vanderbilt University, she went to Paris on a scholarship and studied at the Sorbonne. She went back every year after that, falling in love with the city during one of its most exciting periods of art and literature.

Along with her love of FSU, her devotion to the romantic city is the reason she established the Ada Belle Winthrop-King Endowed Memorial Fund to be used in FSU's Department of Modern Languages and Linguistics in the College of Arts and Sciences. The endowment, administered by the Winthrop-King Institute for Contemporary French and Francophone Studies, supports scholarships to enable students to engage in foreign travel and study and an extensive program of activities that brings to the FSU campus scholars, writers and other public figures from the French-speaking world.

In July 1991, Mrs. Winthrop-King received an honorary doctorate of humane letters from FSU. In 1989, the French government honored her by bestowing on her the rank of Chevalier des Arts et des Lettres.