Mirella Freni is the textbook example of a lyric soprano who expanded wisely to the spinto roles, conserving her voice so that even in her sixties she still possessed enough vocal freshness and bloom that she made a credible Mimi in theaters all over the world. (In Italy, one of her nicknames is "La Prudentissima," or "the most prudent one.") She is also a highly sympathetic actor in both comedies and more serious roles.
In an amusing coincidence, she and Pavarotti shared the same wet nurse as a child (both of their mothers worked in a tobacco factory, making their own milk unsuitable) and she later joked that he obviously got the bigger share of the milk. The granddaughter of Valentina Bartomesi, Freni was a child prodigy, singing "Sempre libera" in her first public performance at the age of ten. At 12, she made her broadcast debut singing "Un bel di" in a radio competition. Beniamino Gigli, a competition judge, warned her that she could damage her voice if she continued to sing opera with her voice still so undeveloped. She waited until she was 17 to begin studying again. Her new teacher was Ettore Campogalliani, whose most-celebrated student had been Renata Tebaldi.
Two years later, in 1955, she made her stage debut as Micaela in Carmen, one of her favorite and most effective roles. At this point, she briefly postponed further career development when she married conductor Leone Magiera and had a child (whom she named Micaela, after her debut role), but resumed singing again in 1958, when she won the Viotti competition in Vercelli, Italy. The prize was the role of Mimi in La bohème in Turin, a role in which she later made her Met, La Scala, Chicago, and San Francisco debuts. In 1960, she made her Glyndebourne debut as Zerlina, in 1961 her Covent Garden debut as Nanetta in Falstaff, and in 1963 her La Scala debut as Mimi in La bohème in the now-famous Zeffirelli production. Herbert von Karajan was the conductor for the La Scala Bohème, and he became one of her prominent supporters; as he did with many singers, he encouraged her to move toward heavier repertoire, such as Desdemona in Otello, which she first sang with him in 1970 and also filmed with Jon Vickers and Peter Glossop in a movie directed and conducted by Karajan. At that time, he declared that he had waited 40 years to hear such a Desdemona. She started to add more of these lyrico-spinto roles to her stage repertoire and also filmed the role of Madama Butterfly with Karajan. However, she absolutely refused to sing the title role of Turandot when he asked her to in 1980, and he subsequently refused to work with her again.
In 1981, she married Bulgarian bass Nicolai Ghiaurov, who encouraged her to examine the Russian repertoire. At first, she began to add Russian songs to her recitals, with his musical and language coaching, and then in the late 1980s, she was ready to sing the role of Tatiana in Eugene Onegin. In 1990, she took on Lisa (The Queen of Spades). In the mid-1990s, she started singing Giordano roles for the first time, not only Fedora, a role typically beloved by divas toward the end of their careers, but the title role of Madame Sans-Gene, a comedic, even occasionally farcical role. In 1990, she received the order Cavaliere della Gran Croce della Republica Italiana and the Légion d'Honneur in 1993.