Our Lady of the Rosary was known for several centuries by the alternate title of “Our Lady of Victory,” in honor of her intercession in a 16th century naval victory which secured Europe against invasion by Islam. "The rosary became the spiritual weapon of the Christians as thousands joined together in prayer on the day of the Battle of Lepanto, October 7, 1571." The Rosary was prayed  from dawn to dusk and victory was won. In honor of her intercession, Pope Pius V named that day a feast day, Our Lady of Victory. This name was later changed to Our Lady of the Rosary, so both titles refer to the same event.
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Another source for history Una Voce Carmel: