The mezzo-soprano Margarete Joswig was born in Mannheim. She studied the piano at the Hochschule für Musik Frankfurt am Main, before entering the opera class, where Elsa Cavelti, Gisela Pohl and Charles Spencer were her teachers. A number of master-classes with Brigitte Fassbaender, Laura Sarti and Montserrat Figueras completed her studies, and in 1994 she joined the ensemble of the Staatstheater Saarbrücken, where she made her début as Hänsel. During the following years she sang Orfeo (Gluck), Dorabella, Idamante (Mozart), Rosina, Isabella, Cenerentola (Rossini), Magdalene (Wagner), Maddalena, Fenena (Verdi), Maria (Gesualdo, Schnittke), and Oktavian (Strauss). From 2000 to 2003 she became a member of the Stuttgart Opera, where she sang major mezzo-soprano rôles. In 2002 she was invited to the Teatro Massimo in Palermo for Victor Ullmanns' opera Der Kaiser von Atlantis. In 2003 she won high acclaim at the Herbstliche Musiktage Bad Urach in the world première of Siegfried Wagner's unknown opera Rainulf und Adelasia, in which she sang the part of Sigilgaita. Other recordings include Durantes Lamentationes Jeremiae Prophetae, and Dvořák's Stabat Mater. She has also appeared in concert and Lieder, with a wide repertoire from Bach to contemporary composers. In 2004 she was a soloist in Mahler's Das Lied von der Erde at the Châtelet in Paris together with the tenor Jonas Kaufmann and the conductor Dietrich Henschel. At the Teatro San Carlo in Naples she appeared as Waltraute in Die Walküre under the baton of Jeffrey Tate.