Case was born in Clinton, New Jersey, on October 29, 1887,[1][2][3][4] and educated by vocal trainer Augusta Öhrström-Renard in New York.

Case made her debut in 1909 at the New Theatre in New York as the Dutch Boy in Werther, and from 1909 to 1916 was a member of the Metropolitan Opera Company.

In her first American performances, she created the roles of Sophie in Der Rosenkavalier (1913) and Feodor in Boris Godunov (1913).

[9] On July 18, 1931, Case married ITT Corporation executive Clarence H. Mackay at St. Mary's Roman Catholic Church in Roslyn, New York, and retired from the stage shortly afterwards.

[10][11] She began to write songs more prolifically in 1936, penning over 50 in two years,[12][7] and sang occasionally at social events.