Pope St. Pius V attributed the victory of the Christian forces at the Battle of Lepanto on October 7, 1571 to the intercession of the Blessed Virgin Mary. That victory inspired him to establish October 7 as the Feast day of Our Lady of Victory (later more popularly known as Our Lady of the Rosary).

 

Pope St. Pius V sought all of Europe to pray the Rosary and ordered a 40 hour vigil-devotion to the Blessed Mother at the time the naval battle was taking place. The Christian naval force was totally outnumbered. But miraculously they defeated the Turks who lost 287 out of their 300 ships.