The vast majority of you know that today is the Feast of Our Lady of the Rosary. And many of you know the history of this Feast. It commemorates not just the Rosary but especially the efficacy of the Rosary in obtaining a great naval victory over an Islamic fleet in 1571, the Battle of Lepanto.
The Catholic Encyclopedia has a summary of the history of the Feast:
It is believed that Heaven has on many occasions rewarded the faith of those who had recourse to [the Rosary] in times of special danger. More particularly, the naval victory of Lepanto gained by Don John of Austria over the Turkish fleet on the first Sunday of October in 1571 responded wonderfully to the processions made at Rome on that same day by the members of the Rosary confraternity. St. Pius V thereupon ordered that a commemoration of the Rosary should be made upon that day, and at the request of the Dominican Order, Gregory XIII in 1573 allowed this feast to be kept in all churches which possessed an altar dedicated to the Holy Rosary. In 1671 the observance of this festival was extended by Clement X to the whole of Spain, and somewhat later Clement XI after the important victory over the Turks gained by Prince Eugene on 6 August, 1716 (the feast of our Lady of the Snows), at Peterwardein in Hungary, commanded the feast of the Rosary to be celebrated by the universal Church.
Under St. Pius V, it was called “Our Lady of Victory.”
Later, the Feast was renamed as “Our Lady of the Holy Rosary.”