The Hoffnung Music Festivals were a series of three humorous classical music festivals held in Royal Festival Hall, London in 1956, 1958 and 1961. They were created by cartoonist and amateur tuba player Gerard Hoffnung.
They included works such as Haydn's Surprise Symphony 'with extra surprises' added by Donald Swann, an 'excerpt from Belshazzar's Feast', with full orchestra and chorus conducted by William Walton himself, which turned out to consist of just a single chord with the word "Slain!", and humorous works specially commissioned from well-known composers of the day.