Each October is dedicated to the Most Holy Rosary. This is primarily because the liturgical feast of Our Lady of the Rosary is celebrated annually on October 7. It was instituted to honor the Blessed Virgin Mary in gratitude for the protection she gives the Church in response to the faithful's praying of the Rosary.
Pope Pius V declared the day — October 7 — as a feast day for Our Lady of the Rosary. To celebrate, the faithful held a rosary procession in Saint Peter’s Square.
Our Mother Mary's presence and protection have immense power—requested, channeled, and honored through the rosary. Her immaculate intercession has won wars and conquered hearts. After establishing the feast day, Pope Leo XIII dedicated the entire month of October to the rosary in 1884.
We know it as one of the most recited and celebrated Catholic prayers—used to implore our Mother Mary for her intercession and blessings. Saint John Paul II expanded on the rosary’s power in his 2002 apostolic letter Rosarium Virginis Mariae, when he announced the Year of the Rosary and the addition of the Luminous Mysteries:
With the Rosary, the Christian people sit at the school of Mary, contemplating the beauty on the face of Christ and experiencing the depths of his love. Through the Rosary, the faithful receive abundant grace, as though from the very hands of the Mother of the Redeemer.