Along with other composers mainly in the Holy Roman Empire and France, he was responsible for certain operatic reforms including reducing the ornateness of style and the primacy of star singers.

In Parma in 1759, he found several noteworthy collaborators, and he was fortunate in finding that the man in charge of opera there was a highly cultivated Paris-trained Frenchman, Guillaume du Tillot, who had the complete cultural portfolio among all his other responsibilities as Don Felipe's First Minister.

To judge from the general stylistic influence in terms of grand scenic effects, and from some specific musical borrowings, Traetta had access in Parma to copies and reports of Rameau's operas.

Carlo Innocenzo Frugoni, Traetta's librettist in Parma, completely reworked the original French version by abbé Pellegrin, which itself had been based on Racine, in its turn stemming ultimately from ancient Greek roots–the Hippolytus of Euripides.

Frugoni kept certain key French elements: the five-act structure as against the customary three; the occasional opportunities for French-style spectacle and effects and, in particular, the dances and divertissements that end each of those five acts; and more elaborate use of the chorus than, for instance, in Hasse and Graun and Jommelli.

According to the Traetta Association in Bitonto, he had left Saint Petersburg under threat of assassination by the empress—it seems he was enraged that she insisted on a happy ending for Antigona, and in revenge put music for Polish independence into the final chaconne.