Composers in training write themes and variations to exercise their creativity. They choose an original or pre-existing melody and vary it by breaking it apart, turning it upside down or inside out, restating it in different major and minor keys, and altering the rhythm and the harmony. It is an ancient form from before music notation existed and common in the music of many cultures. J.S. Bach’s Goldberg Variations, Rachmaninoff’s Paganini variations, and Beethoven’s Diabelli Variations (a musical joke in which Beethoven varied a trite little waltz 33 times) are famous sets of theme and variations. Brahms composed several variations during his life including a youthful one on a theme by Robert Schumann and dedicated to Clara Schumann.
Variations on a Theme by Haydn is a masterpiece of variation techniques. Brahms believed the theme he chose for this work to be by Haydn, but it is probably not; its origins remain uncertain today. The “Brahms Haydn Variations” as it is familiarly called started life as a work for two pianos. Brahms orchestrated it in 1873 to make the version most heard today. What attracted Brahms to this particular theme is revealed in his variations of it.
In the first variation Brahms plays with the four repeated chords that end the statement of the theme, while in the second variation the dotted rhythm permeates the texture. In the third variation the dotted rhythm is smoothed out to form a new theme although still following the main theme’s harmony. An astounding feature of this work, and one of the reasons it has so much to teach composers, is the variety of moods the composer is able to extract from the original chorale: the scherzo-like vivace of variation five; the pompous brass march that turns a little frightening in variation six; and the stately, elegant grazioso of variation seven. Brahms closes this work with a long solemn rumination which slowly transforms little by little into a festival celebration of the original chorale theme. His ruminations are not random but organized into a chaconne, a procedure he also used for the finale of his Fourth Symphony; the bass of the chorale is repeated over and over again with more variations of the theme climaxing to an arousing statement of the four chords closing the original melody and now the composition.