About a decade ago I wrote a series of articles detailing the transition period from 1964-1970, as experienced in the United States. Some of the recollections here have been inaccurate. While there were some variations in timing based on one’s diocese, this is the timeline:
28 Apr 64: On this date, the words for the administration of Communion became Corpus Christi, to which the communicant responded Amen. (Some dioceses began this change several months after this date.)
29 Nov 64: On Advent Sunday (the beginning of the 1965 liturgical year), vernacular readings were permitted as the official liturgical texts–using the Confraternity translation–along with the use of commentators to explain the various parts of the Mass. Also permitted was the recitation of the antiphons and the Kyrie, Gloria, Credo, Sanctus and Agnus Dei. While there was no one date on which the altars were “turned around,” in most places this occurred, through the use of temporary altars, on or around this date.
7 Mar 65: The prayer at the foot of the altar were shortened, with the elimination of the psalm Judica me, as were the last gospel and Leonine prayers after Mass. Concelebration was permitted for Maundy Thursday Masses, and the first (but very limited) permission for communion under both kinds was given. Prayers of the faithful and offertory processions began to also be permitted. These changes and the ones immediately before it together constitute what is often called the 1965 missal, though no such edition was actually promulgated, as the process of reform was still a work in progress.
27 Mar 66: All audible parts of the Mass were permitted in the vernacular (including the collects, so for many, the response And with your spirit began to be used here), while all silent parts were retained in Latin. Thus, everything the people heard was in English, while the priest’s prayers before the gospel, while blessing incense, during the offertory, the entire Canon of the Mass, the priest’s prayers after the Our Father and before communion, as well as after communion and before the final blessing, were still recited in Latin, in the Tridentine format. There were still two readings at Mass.
22 Oct 67: Permission was given for the Canon of the Mass to be recited aloud and in the vernacular. The rubrics were simpified in June, reducing the number of genuflections and signs of the cross made by the priest, and many places implemented those changes along with the vernacular, audible Canon of the Mass.
1 Dec 68: Three additional eucharistic prayers were introduced. This change and the one before it represented huge changes in the Order of the Mass. The EPs had been introduced in August, and dioceses phased them in throughout the fall, until Advent Sunday, the mandated date of implementation.
30 Nov 69: The new missal began to be used. This included the now-familiar ICEL translation of the Mass, which moved away from the interim forms that had been used for the previous five years, which in many ways would resemble the current translations. Three readings were now read at Sunday Mass, with a responsorial psalm replacing the former gradual psalm. The missal had been promulgated in April, 1969, and its use mandated by Advent Sunday, though this was later extended to 1 Jan 71.
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