The Battle of Lepanto was a crucial conflict between the Christians and the Ottoman Turks, one of the greatest naval battles of all time. The Christian lands around Greece and the Eastern Mediterranean were constantly getting sacked by Muslim pirates, and Imperial warships were ravaging the land. At this point in time, Pope Saint Pius V saw it appropriate to raise a Crusade against these heathen Muslims. After raising a Crusade, he asked every non-combatant across the whole Christian world to pray the Rosary.
Even after this call to arms, the Christian fleet at Lepanto was greatly outnumbered by the Ottoman Turks. The Crusaders got on their knees and began to pray the Rosary. Soon after, the Christians and the Muslims were immersed in a bloody battle. Thus it was that on October 7, 1571, the Christian fleet was blessed with a miraculous victory. Pope Saint Pius V immediately dedicated the victory to Our Lady, establishing October 7 as “The Feast of the Most Holy Rosary.