Mathias Zachariassen was born in Danderyd, Sweden, in 1968. Educated at the Stockholm College of Opera, with Gunnar Suttner and Nicolai Gedda, he made his international debut as Eurimedes in Telemann´s Orpheus at the LANDESTHEATER INNSBRUCK in 1994, conducted by René Jacobs. In 1999 he received the Eberhard Waechter Medal for his interpretations of Roudi in Rossini´s Guillaume Tell at the WIENER STAATSOPER, conducted by Fabio Luisi, and of David in Wagner´s Meistersinger von Nürnberg at the WIENER VOLKSOPER, conducted by Ascher Fisch. In 2001 he made his debut at the METROPOLITAN OPERA as David in Meistersinger von Nürnberg, conducted by James Levine.
He made his debut at the WIENER STAATSOPER in 1998 as Sänger in Strauss´ Der Rosenkavalier, and has since sung a wide repertoire at this house, including Tamino (Mozart: Die Zauberflöte), Rinuccio (Puccini: Gianni Schicchi), Steuermann (Wagner: Der fliegende Hollender), Jaquino (Beethoven: Fidelio), and Rosillon (Lehár: Die Lustige Witwe).
Furthermore he was a guest at the BERLINER STAATSOPER, the THEATRE DE LA MONNAIE in Brussels, the GLYNDEBOURNE FESTIVAL, as well as Paris (BASTILLE and THEATRE DES CHAMPS ELYSSEES), Frankfurt, Stuttgart, Zürich, Stockholm, Oslo, and the WAR MEMORIAL OPERA HOUSE in San Francisco.
Further important roles of the artist are: Il Duca di Mantova (Verdi: Rigoletto), Alfredo (Verdi: La Traviata), Nemorino (Donizetti: L´Elisir d´amore), Tom Rakewell (Stravinskij: The Rake´s Progress), Prologue and Peter Quint (Britten: The Turn of the Screw), Lenskij (Tjajkovskij: Eugen Onegin), Hoffman (Offenbach: Les Contes d´Hoffmann), Ferrando (Mozart: Cosi fan tutte), Belmonte (Mozart: Die Entfürung aus dem Serail), Don Ottavio (Mozart: Don Giovanni), Idamante and Arbace (Mozart: Idomeneo) and the title role of Mozart´s Mitridate.
In 2003 he made his composer debut, performing himself songs with lyrics by Nelly Sachs at the Centre Culturel Suèdois in Paris.