The William Tell Overture is the overture to the opera William Tell, whose music was composed by Gioachino Rossini. William Tell premiered in 1829 and was the last of Rossini's 39 operas, after which he went into semi-retirement. The overture is in four parts, each following without pause.
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William Tell is a French-language opera in four acts by Italian composer Gioachino Rossini to a libretto by Victor-Joseph Étienne de Jouy and L. F. Bis, based on Friedrich Schiller's play William Tell, which, in turn, drew on the William Tell legend. The opera was Rossini's last, although he lived for nearly 40 more years. Fabio Luisi said that Rossini planned for William Tell to be his last opera even as he composed it. The often-performed overture in four sections features a depiction of a storm and a vivacious finale, the "March of the Swiss Soldiers".
The above text from the Wikipedia article "William Tell (opera)" text is available under CC BY-SA 3.0.