The following history gives a concise view of how the season of Advent developed in the life and history of the Church.
In 490, Bishop Perpetuus of Tours officially declared Advent a penitential season in the Frankish Church of Western Europe, ordering a fast on three days of every week from November 11 (the feast of St. Martin of Tours) till Christmas. This forty days' fast, similar to Lent, was originally called Quadragesima Sancti Martini: (CP notes that this does NOT translate as "40 days of the Holy Martini season!") the Forty Days of Saint Martin - or - St. Martin's Lent. The readings for the Masses in this season were taken from the liturgies of Lent.
By contrast, the Advent season of the Roman liturgy, developing a century after that of the Frankish Church, was a non-penitential, festive and joyful time of preparation for Christmas. When the Church unified the liturgical season, the non-penitential nature of the Roman Advent conflicted with the longer and penitential Gallic Advent. By the thirteenth century a compromise was reached, which combined the fasting and penitential character of the Gallic observance with the Mass texts and shorter four-week cycle of the Roman Advent liturgy. The liturgy of Advent remained substantially unaltered until Vatican II mandated a few minor changes to more clearly delineate the spirit of the Lenten and Advent seasons.
Jennifer Gregory Miller Jennifer G. Miller