Our Lady of the Rosary

The feast of the Holy Rosary was instituted by Pope Pius V to celebrate the anniversary of the defeat of the Turkish fleet at the battle of Lepanto on the first Sunday in October 1571, which ended the threat of Muslim domination of the Mediterranean and was ascribed in part to the prayers and processions of the Rosary confraternity in Rome. Later the feast was moved to the fixed date of 7 October.

I sought out solitude to pray my devotions, and they were many, especially the rosary, to which my mother was very devoted; and she made us devoted to it too.  (St Teresa of Avila, The Book of her Life, ch 1)