Born as Katharina Magdalena Josepha Cavalier[N 1] in Lichtental, Vienna, Cavalieri studied voice with composer Antonio Salieri.

Similarly Wolfgang Amadeus Mozart wrote the role of Konstanze in his Singspiel Die Entführung aus dem Serail for her, which she premiered on 16 July 1782.

On 1 June 1785 she sang the role of Enrichetta in the première of Stephen Storace's Gli sposi malcontenti.

Cavalieri is a nonspeaking role in Peter Shaffer's play Amadeus and she is portrayed as Salieri's love interest.

In the film, it is suggested that Cavalieri and Mozart had an affair during the rehearsals of Die Entführung aus dem Serail.