Keyboard music in its broadest sense forms the core of Franz Xaver Wolfgang Mozart’s compositional activities. (…)
Interestingly, already the earliest compositions show a style of their own. Even the so-called Rondo in F major WV VII:1 (actually a movement in sonata form) soon leaves the paths of Wolfgang Amadeus Mozart and Joseph Haydn which would have been the most imminent models. The Rondeau in F major Op. 4 is similar in style to this first compositional attempt, but it is definitely more polished and surprises by a wealth of different keyboard techniques and by sophisticated modulations.
The intentions of the composer finally become evident in the Piano Sonata in G major Op. 10, the most extended and perhaps also the most ambitious piano work of the composer, then still just 16 years old. The model of Beethoven is only evident in the four-movement plan with a minuet or scherzo as part of the cycle, but none of the movement even tries to imitate Beethoven’s heroic style. Like in many works of Schubert (who at that time had not yet started his musical career) the influence of dance music can be felt, particularly in the third and fourth movements. (…)
The small number of works and their limited distribution already during the composer’s lifetime make it difficult to ascertain the place of Franz Xaver Mozart in the history of keyboard music. It appears, however, that he was one of the first who contributed to what may be called a Polish or Russian style. Many of the keyboard works he composed in Podkamień, Smolanka and Lemberg are based on Slavic melodies, some of which attracted the curiosity of other Western composers as the example of Beethoven’s Rasumowsky or Russians Quartets Op. 59 (1806) vividly demonstrates. Franz Xaver Wolfgang composed an entire series of sets of variations on Russian themes, including the Variations on a (hitherto unidentified) Russian Song which was published during his concert tour of 1819–21 by August Cranz in Hamburg as his Op. 20 and which are presented here for the first time.
The variations were long believed to have been lost, but a copy of the original print could recently be located in the Austrian National Library where it had erroneously been catalogued under the name of his father and thus escaped the attention of Franz Xaver Mozart scholars. They demonstrate that Franz Xaver Mozart did no longer follow the model of his father with a somewhat foreseeable sequence of melodic variations as one could observe in his earliest variations. Rather – like Beethoven from his Opp. 34 and 35 (1802) on – Franz Xaver Mozart aims at a series of character pieces based on a common sequence of harmonies. The variations are technically demanding and we can easily imagine how Franz Xaver Wolfgang Mozart diverted and surprised his audiences in many European cities with folkloristic variations of this kind as encore pieces after having presented piano concertos of his father’s or his own invention.
A consequent further step in this direction are the twelve polonaises for piano solo that Franz Xaver Wolfgang wrote mainly during his Lemberg years and published in three instalments as his Opp. 17, 22, and 26. From the thematic catalogue that Franz Xaver Wolfgang – like his famous father – compiled over many years it becomes evident that neither of the sets of Polonaises forms a cycle in the strict sense, but that the works originated one by one over an extended period of time. The Polonaises Op. 22 are arguably the best keyboard works of Franz Xaver Mozart and they are rightly called “mélancoliques”. (…) Only here he was nothing but himself – entirely freed, despite the sad undertones, from the life-long burden of his father’s name!