When Johannes Brahms composed his «Variations on a Theme by Joseph Haydn» in 1873, he was confident he knew who had originally written the «Chorale St. Antoni». Three years previously, Johannes Brahms had tracked down this magical choral theme from Haydn’s Divertimento in B flat major for eight wind instruments in the archive of the Gesellschaft der Musikfreunde in Wien (Society of Friends of Music in Vienna). But today we are almost certain it was written by a student of Haydn. One thing’s for sure: the eight orchestral variations by Brahms with their magnificent passacaglia at the end also helped bring great fame to the chamber piece that was their source. The variations are complemented by three bestsellers: Brahms’ «Hungarian Dances», originally intended for piano four hands, ensured the composer’s breakthrough.