He excelled at the violin and organ from an early age, received his first musical training from his family and local musicians, the organist Anton Erban being one of his most prized mentors.
He was also taught German from an early age, as this was required for someone wishing to make a career in music within the Habsburg empire.
[4] By the age of 21 Wanhal must have been well under way to become a skilled performer and composer, as his patron, the Countess Schaffgotsch, took him to Vienna as part of her personal train in 1760.
There he quickly established himself as a teacher of singing, violin and piano to the high nobility, and he was invited to conduct his symphonies for illustrious patrons such as the Erdődy families and Baron Isaac von Riesch of Dresden.
Baron Riesch sponsored a trip to Italy in 1769, so that Wanhal could learn the Italian style of composition, which was very much in fashion.
[6] The details of Wanhal's journey to Italy are scant, but it is known that he met his fellow Bohemians Gluck and Florian Gassmann in Venice and Rome respectively.
During this period he is supposed to have acted occasionally as a de facto Kapellmeister for Count Erdődy in Varaždin, Croatia, although the small number of compositions by him remaining there suggests that this was not the full-time role that would have been expected if he had worked with Riesch; Vanhal might have preferred such employment with the Count precisely because of its part-time nature.
Many of Wanhal's symphonies are in minor keys and are considered highly influential to the "Sturm und Drang" movement of his time.
"[Wanhal] makes use of repeated semiquavers, pounding quavers in the bass line, wide skips in the themes, sudden pauses (fermatas), silences, exaggerated dynamic marks ... and all these features ... appear in Mozart's first large-scale Sturm und Drang symphony, no.
This means that his late Masses are both testaments to a genuine personal faith, and evidence of how lucrative his focus on incidental piano music must have been.