After more than 400 performances at the Vienna State Opera, where her interpretations of many great roles, particularly those from Wolfgang Amadeus Mozart and Richard Strauss, won her wide acclaim and appreciation, Della Casa left the opera world in 1974, apparently weary of the music business.
The Vienna State Opera said Della Casa died Monday at the age of 93 in the northern Swiss town of Muensterlingen, along the lakeshore.
Salzburg Festival President Helga Rabl-Stadler recalled Della Casa's performances as "sublime moments for which she was celebrated by audiences and critics alike." To mark her death, Rabl-Stadler added in a statement, the festival hung a black flag that waved as "a tiny sign of our sorrow and gratitude."
Della Casa was born near the Swiss capital Bern in 1919 and later trained in Zurich.Her first performance, during World War II, came as Giacomo Puccini's "Madame Butterfly" at the Solothurn-Biel Municipal Theater. She would go on to perform on many of the world's great opera stages including the Metropolitan Opera, the Royal Opera House and La Scala.
In her performances of Richard Strauss's "Arabella," including as Zdenka at the Salzburg Festival in 1947 and as Arabella at the Royal Opera House in London's Covent Garden in 1953, she wowed crowds and became identified with the opera because of what critics celebrated as a natural grace in her singing and her beauty. In 1953, she also debuted at the Metropolitan Opera House in New York as Countess Almaviva in Mozart's "The Marriage of Figaro."
She became known as a specialist in Mozart and Strauss, singing regularly in Europe and the United States.
Della Casa retired to her castle along Lake Constance in northern Switzerland, where she lived with her husband, journalist and violinist Dragan Debeljevic, and their daughter, Vesna. They couple were married in 1949.