Theater auf der Wieden
In his youth Seyfried served as the assistant conductor for Emanuel Schikaneder's opera troupe at the Theater auf der Wieden in Vienna, becoming musical director in 1797 and serving (in its new building, the Theater an der Wien) until 1826. His memoirs offer accounts of the first production, under Schikaneder's auspices, of Mozart's "The Magic Flute", as well as a curious anecdote concerning the composer's death a few weeks later; see Death of Mozart.