Des Knaben Wunderhorn
Since the days of the Carlsbad Decrees and the Age of Metternich, "Die Gedanken sind frei" was a popular protest song against political repression and censorship, especially among the banned Burschenschaften student fraternities. In the aftermath of the failed 1848 German Revolution the song was banned. The Achim/Brentano text was given a new musical setting for voice and orchestra by Gustav Mahler in his 1898 "Des Knaben Wunderhorn" collection.