In 1709, the thirty-year-old Vivaldi committed this, his second work after the Sonate a tre published in 1705, to the printers, determined to re-confirm his worth as a composer. The visit to Venice, at the end of 1708, by Frederick IV of Denmark and Norway (who heard Vivaldi’s music and the “putte” musicians at the Ospedale della Pietà) was an opportunity to present a northern European patron a work for the violin, an instrument on which Vivaldi was a famous virtuoso, in the hope of obtaining appointments abroad. In the first few years of the 18th century, it was normal for all young violinists to grow up playing the famous Sonatas for violin by Arcangelo Corelli (Opus 5, published in 1700) and to consider them to be a suitable model to imitate, or perhaps to be a restriction to their creative talent. This was certainly not Vivaldi’s case. In fact what emerges from Op. 2 is a combination of Corelli’s style and Vivaldi’s irrepressible nature, which was to be fully evident soon afterwards in the Estro Armonico concertos, a work that also became a model of style (for Bach too). When listening to Vivaldi’s kinds of harmonic progressions, it is obvious that they are often identical to Corelli’s; but the refined taste and attention to the proportions determined by Corelli’s “classicism” is influenced skilfully by Vivaldi’s irrepressible ideas.