In 1951, Ruth Stewart received two Fulbright scholarships to pursue a voice major at St. Cecelia Conservatory, Rome with maestra Marie Teresa Pediconi.
After the first of the five concerts given for Count Guido Chigi-Saracini at the Chigiana Academy, Siena, one critic wrote that "Ruth Stewart immediately won the admiration of the public with her extraordinary personality.
Ruth Stewart joined Texas Southern University in the spring of 1954 as an instructor of voice, director of the Women's Glee Club and later became co-director of the Opera Workshop.
In 1965, with the assistance of Mr. Clifford Smith, a local electrical contractor, she organized and conducted the highly successful choral group The Men of Houston, made up of many fine singers in the community.
During her 29-year tenure at Texas Southern University she co-produced several operas, including Cavalleria rusticana, Madama Butterfly, La bohème, Amahl and the Night Visitors, The King and I, Requiem (Verdi), and Messiah (Handel).