Before then, Latin was the vernacular in the West. Popes Gregory and Pius V only codified existing practices. They did not create a "new order" as did Pope Paul VI.
Yes it was and here is an interesting tidbit from the from the Catholic Encyclopedia:
"Until the middle of the third century the Christian community at Rome was in the main a Greek speaking one. The Liturgy was celebrated in Greek, and the apologists and theologians wrote in Greek until the time of St. Hippolytus, who died in 235. … Greek was the chosen language of the clerics, to begin with, but Latin was the more familiar speech for the majority of the faithful, and it must have soon taken the lead in the Church, since Tertullian, who wrote some of his earlier works in Greek, ended by employing Latin only. ….But even before these writers various local Churches must have seen the necessity of rendering into Latin the texts of the Old and New Testaments, the reading of which formed a main portion of the Liturgy. This necessity arose as soon as the Latin speaking faithful became numerous,"
I wonder if there was an uproar from the traditionalists when Greek was abandoned in favor of the more popular Latin?