BLESSED ALAN says that a certain Cardinal Pierre, whose titular Church was that of St. Mary-beyond-the-Tiber, was a great friend of Saint Dominic's and had learned from him a deep devotion to the Most Holy Rosary. This resulted in his loving it so much that he never ceased singing its praises and encouraging everyone he met to embrace it.
Eventually he was sent as Legate to the Holy Land to the Christians who were fighting the Saracens. So successfully did he convince the Christian army of the power of the Rosary that they started saying it one and all to storm Heaven for help in a battle in which they knew they would be pitifully out-numbered. This resulted in victory for them, and three thousand Christians triumphed over an enemy of one hundred thousand.
As we have seen, the devils have an overwhelming fear of the Rosary. Saint Bernard says that the Angelic Salutation puts them to flight and makes all Hell tremble.
Blessed Alan says that he has seen several people delivered from Satan's bondage after taking up the Holy Rosary, even though they had previously sold themselves to him in body and soul by renouncing their Baptismal Vows and their allegiance to Our Lord Jesus Christ.