Roots away, me boys, roots away! "The roots of the Tridentine (the Canon, etc.) are recorded in the Leonine, Gelasian, and Gregorian Sacramentaries which long predate Alcuin." Yes indeedy. OK, so he did not invent the liturgy for Aachen out of cloth. But it was indeed Alcuin who did the dirty deed and Henry II who shoved it right down the throat of the Roman pope.
Details are all layed out for you in glorious detail by Gerald Eliard,S.J., Master Alcuin, Liturgist: A Partner of Our Piety (Chicago, Loyola University Press, 1956).
Read and weep baby!
Oh, wait, St. Basil also changed the liturgy of St. James. Yes, we must consign St. Basil to the depths of Hell with St. John Chrysostom. Yes, only the pure and unchanged liturgy of St. James will do.