One thing is clear: those that were, were spearheaded by a group of liturgists and theologians from the Rhine Valley.
Catholic Mass Unchanged Since 600 AD
Up until the 1960s, the Roman Rite Mass had remained essentially unchanged --except for minor local variances -- from the time of St Pope Gregory the Great (590-604). The Council of Trent (1545-1563) decreed that the Mass was to be celebrated uniformly and so St Pope Pius V in 1570 published a revised missal by the Bull Quo Primum.
The Missal of Pius V continued in use with very minor changes until the John XXIII Missal of 1962.
The Roots of Change
A torrent of questions remain basically unanswered. What led to the revolutionary changes in the Mass, post-Vatican II? Why have the priest face the people? Why term the priest no longer a ‘celebrant’ but a ‘president’? Why change all the ancient prayers to the vernacular? Why delete the prayers at the foot of the altar? Did all of this really start at Vatican II, as many believe? Or did it actually start earlier?
Some say these liturgical changes began with St Pope Pius X on November 22, 1903 with his motu proprio 'Tra le sollecitudini'
“It being our ardent desire to see the true Christian spirit restored in every respect and preserved by all the faithful, we deem it necessary to provide before everything else for the sanctity and dignity of the temple, in which the faithful assemble for the object of acquiring this spirit from its indispensable fount, which is the active participation in the holy mysteries and in the public and solemn prayer of the Church.”
Tra le sollecitudini, in short, helped reform liturgical music with active participation of the faithful. Pius X’s reform energized others to action.
Father Romano Guardini, an Italian by birth who was raised in southern Germany, may have been the genesis for what later became known as the ‘liturgical movement.’ This was an effort to enhance the appreciation and experience of worship with one goal: to enable the active participation of the faithful in the liturgy.
Guardini’s liturgical movement spread to the Rhine. Concentrated mostly in France and Germany, this pre-World War I liturgical movement was made up of academics, scholars, monks, priests and visionaries. There was little in the way of representation from the laity in the pews.
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