Concertos for Oboe, Strings and Continuo

As far as Vivaldi’s vast opus is concerned, his concertos for oboe, strings and basso continuo present us with more doubts than convictions.
The first doubt concerns their number: the most up-to-date edition of the Ryom catalogue lists twenty, and also includes three others for two oboes, two for violin and oboe, one for oboe and bassoon and eight for ‘Per molti Istromenti’, in which the oboe is part of the concertino, but at least two of them are considered spurious works.
Further doubts refer to when and for whom they were written.
A possible beneficiary, apart from the girls at the Ospedale della Pietà, was the Saxony Court, as can be seen from the note ‘p[er] Sas[soni]a’ (for Saxony) written on the manuscript of Concerto RV.455.
There is no doubt that Vivaldi was completely captivated by the rich and warm tone and multiple technical and expressive abilities of the oboe.
For some time it had been an orchestral instrument, but then progressed from simply supporting the strings, to being an important solo instrument in its own right.
The first concertos for oboe were presumably composed just after 1710, when Venice was still dominated by composers from the other side of the Alps.
In 1715 Tomaso Albinoni composed the first concertos written in Italy for the oboe, and Vivaldi followed this up by imposing a typically Italian style, based on irrepressible vitality and virtuosic passages in the fast movements, and calm, unmistakably theatrical, melodies in the andantes.
Another Vivaldian characteristic was that he seemed to have been writing for the violin: this is most evident in the very long phrases that the oboist is asked to play without taking a breath.