The month of October each year is dedicated to the Most Holy Rosary. This is primarily due to the fact that the liturgical feast of Our Lady of the Rosary is celebrated annually on October 7th. It was instituted to honor the Blessed Virgin Mary in gratitude for the protection that she gives the Church in answer to the praying of the Rosary by the faithful.
The feast was introduced by Pope St. Pius V (1504-1572) in the year 1571 to commemorate the miraculous victory of the Christian forces in the Battle of Lepanto on October 7, 1571. The pope attributed more to the "arms" of the Rosary than the power of cannons and the valor of the soldiers who fought there.
Legend tells us that the Rosary as a form of prayer was given to St. Dominic (1170- 1221) by Mary, the Mother of Our Lord, who entrusted it to him as an aid in the conflicts with the Albigensians. The Dominican pope, St. Pius V, did much to further the spread of the Rosary and it thereafter became one of the most popular devotions in Christendom. It was the same Pope St. Pius V, who in 1569 officially approved the Rosary in its present form with the Papal Bull, CONSUEVERUNT ROMANI PONTIFECES. It had been completed by the addition of the second half of the "Hail Mary" and the "Glory be to the Father" at the conclusion of each mystery.
Current scholarship traces the development of the Rosary to the High Middle Ages where it came into being in various medieval monasteries as a substitute for the Divine Office for the lay monks and devout lay persons who did not know how to read. Instead of the 150 psalms, they would pray 150 "Our Fathers" counting them on a ring of beads known as the crown or "corona". With the growth of popularity of Marian devotion in the twelfth century, the "Psalter of the Blessed Virgin Mary" developed now substituting 150 "Hail Marys" in place of the "Our Fathers." From the 16th to the early 20th century, the structure of the rosary remained essentially unchanged. There were 15 mysteries, one for each of the 15 decades. In the 20th century the addition of the Fatima Prayer to the end of each decade became more common. There were no other changes until 2002 when John Paul II instituted five optional new Luminous Mysteries.
By Fr. M. Mauriello