Beethoven's "Missa solemnis"

While composing his Missa solemnis, Beethoven looked to the past.  He obtained a copy of the score to J.S. Bach’s unpublished B Minor Mass, and studied the sacred music of C.P.E. Bach. After countless sketches and spiritual preparation, Beethoven composed this work for large orchestra and chorus, dedicating more time to it than any other of his works. Written simultaneously with the Symphony No. 9, Missa solemnis is considered one of the most significant mass settings in classical music.