He gave important premieres in France, Germany, England and the United States, and played Siegmund in the first complete production of Der Ring des Nibelungen (Bayreuth Festspielhaus 1876).
Born in Erxleben, in the Prussian Province of Saxony (now Saxony-Anhalt), Niemann lost his father (an innkeeper) at an early age and was brought up by his mother, a woman 'of almost unwomanly hardness' who lived to be ninety.
He received training from Fritz Schneider (director of the ducal Hofkapell), from Albert Nusch and from Gilbert Duprez in Paris.
From 1859, Wagner had involved Niemann (then at Hanover) in his plan to form a model German company to perform some operas, including Tristan und Isolde, in Paris in 1860.
[6] However, Paris issued an imperial command for Tannhäuser, and Niemann obtained a nine-month contract to join these rehearsals in September 1860.
[8] He had learned that a Parisian faction intended to disrupt the production, and disloyally went through with it presenting himself as the unlucky artist involved in a work unworthy of his powers.
[9] Baudelaire wrote that Niemann had 'sung out of tune with deplorable assiduity', and condemned 'his weaknesses, his swoons, his tantrums of a spoiled child.
[15] Lilli Lehmann wrote of him, 'never since have I heard or seen a Siegmund to compare with him... His intellectual power, his physical impressiveness, his incomparable expression were superb beyond words.'
Saint-Saëns, however, considered that since the Paris 1861 Tannhäuser, time had eaten away Niemann's high notes, and he could no longer sing piano or legato.
[3] In New York, he also sang Siegmund, John of Leyden in Le prophète, Tannhäuser, Lohengrin, Florestan (in Fidelio), and Eleazar in La juive.