sentences:  From 1859 to 1870 and again from 1873 to 1877 he conducted the concerts of the Gesellschaft der Musikfreunde, which under his energetic leadership became events of prime importance.In 1866 he was made chief court Kapellmeister and from 1871 to 1875 he was director of the Imperial Opera, resigning over intrigues and annoyances he could not tolerate.He was a great supporter of the music of Franz Schubert, and conducted the premiere of his "Unfinished" Symphony in 1865.