|Image via Das Wik|
Josef Mysliveček was a composer from Bohemia in the Austrian Empire. Giving up a promising (if boring) career in industry, he traveled to Italy to study composition, becoming known as Il Boemo ("The Bohemian"). It was here that he met the 14 year old Wolfgang Mozart and his father. He quickly became a close family friend, and Mysliveček's already well developed musical style became a major influence on Mozart, and therefore on the entirety of Classical music.
But as with Mozart, Mysliveče's musical brilliance did not extend to the fiscal realm. Successful with a whole series of operas and other compositions, he spent freely and ended his days in poverty. This likely was an influence in his falling out with the Mozart family, after he more or less stiffed them on an opera commission. His peccadilloes also included a voracious taste for the ladies of Rome, and may have suffered from syphilis(according to letters from the Mozart family).
But his musical brilliance is unmistakeable, as is his influence on the young Mozart. It is a safe bet that Classical music would not have developed the way it did without his groundbreaking experiments.
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