> (This lightening influence was a general gift from Italy to its northern neighbor, and benefitted Mozart and others as well.)
Well, there was also Corelli, who was the other early source of the Classical symphony. His more conservative style was popular in England and Rome (part of Italy, no?), where Vivaldi's concerto style was taken up in northern Italy, France and Germany, notably by Bach's sons.
Generally, I think the "north" was capable of "lightening" itself up. Take the Waltz:
"The simple, unsophisticated form of these German dances, as opposed to the stateliness of the minuet, helped them to gain popularity and wide social acceptance, and the gliding and whirling associated with the description ‘walzen’ particularly helped the progress of what was eventually to be known as the waltz. In Die Leiden des jungen Werther (1774), Goethe described how, after Lotte had told her cavalier that she would very much like to dance ‘à l’Allemande’, she and Werther ‘soon took to waltzing and circled round each other like the spheres’.
"But the increasing popularity of the waltz brought with it objections: on the one hand on medical considerations, because of the speed with which the dancers whirled around the room, and on the other on moral grounds because of the closeness with which the partners held each other. In 1797, in Halle, Salomo Jakob Wolf published a pamphlet entitled Beweis dass das Walzen eine Hauptquelle der Schwäche des Körpers und des Geistes unserer Generation sey (‘Proof thatwaltzing is a main source of the weakness of the body and mind of our generation’), and in an account of a journey through parts of Germany, Hungary, Italy and France in 1798 and 1799 Ernst Moritz Arndt wrote of ‘the erotic nature’ of the waltz as danced in some parts:
'The male dancers grasped the long dresses of their partners so that they would not drag and be trodden upon, and lifted them high, holding them in this cloak which brought both bodies under one cover, as closely as possible against each other, and in this way the whirling continued in the most indecent positions; the supporting hand lay firmly on the breasts, at each movement making little lustful pressures; the girls went wild and looked as if they would drop. When waltzingon the darker side of the room there were bolder embraces and kisses. The custom of the country; it is not as bad as it looks, they exclaim: but now I understand very well why here and there in parts of Swabia and Switzerland thewaltz has been prohibited.'"
(from Oxford Music Online)
The Ottomans were interested in the Waltz too, as these recordings of Ismail Dede Efendi testify: