Karl Gustav Gerhard Nienstedt was born in Hanover. He studied voice at the
Opernschule there with
Otto Köhler. His first engagement was in 1954 at the ''
, where he made his debut as the king in Lohengrin. He sang in Gelsenkirchen from 1955 to 1959, with the '' to 1961, with the
Cologne Opera from 1962 to 1972, and with the
Frankfurt Opera. In 1965, he participated in the premiere of
Bernd Alois Zimmermann's '''' in Cologne, singing the part of Haudy. He performed also in the Frankfurt production of the opera. Nienstedt performed at the
Bayreuth Festival every summer from 1962 to 1976, in 14 parts such as Klingsor in
Parsifal, Gunther in
Götterdämmerung, Donner in '
, Hunding in ', Fafner (the dragon) in
Siegfried, and Kothner in ''''. He was a member of the
Vienna State Opera from 1964 to 1973, became an Austrian citizen and was awarded the title ''
. He performed at the in Brussels several times between 1964 and 1983, including the parts Orest in Elektra'' by Strauss, Rocco in Beethoven's
Fidelio, Marke in ''
and Gurnemanz in Parsifal
. He sang in 1968 at the '' the part of King Wladislaw in Smetana's
Dalibor, conducted by
Rafael Kubelik, and in 1971 at
La Scala the title role of Alban Berg's
Wozzeck, conducted by
Claudio Abbado and alongside
Evelyn Lear as Marie. In concert, Nienstedt sang the bass part in Bach's
St Matthew Passion at the 1977 .
Herbert von Karajan conducted the
Wiener Singverein and the
Berlin Philharmonic, with
Peter Schreier as the
Evangelist and
Jose van Dam as the . In 1979 he performed in the premiere of the three-act version of Alban Berg's
Lulu the parts of the animal tamer and Rodrigo, staged by
Patrice Chéreau and conducted by
Pierre Boulez, a performance recorded on DVD. Again with Boulez, he was in 1987 a soloist in Schoenberg's '''' in the
Royal Albert Hall. From 1973, Nienstedt worked in the direction of the
Bielefeld Opera, of the '
from 1981 to 1985. and of the ' from 1985 to 1987. Nienstedt was director and artistic director of the '''' from 1982 to 1988. He appeared occasionally, for example in 1980 as the narrator in a performance of Honegger's '''' by the and the in the , with soloists
Klesie Kelly and
Claudia Eder. As a teacher, he taught voice at the opera class of the
Peter Cornelius Conservatory of
Mainz, from 1987 acting at the opera class of the '
(now Hochschule für Musik Detmold), and as professor of voice at the ' (now ''''). He died in Vienna. == Selected recordings ==