To say that Christendom was in dire straights would be an understatement.
In the late 16th century, Christian Europe was weak and splintered. Politically, Europe was just a collection of small, warring kingdoms. And their fragile unity in the Catholic faith had just been broken by the Protestant Reformation, which was now in full swing across the continent.
The Ottoman Empire, on the other hand, was strong and growing, having not lost a significant naval battle in a hundred years. Its forces had already conquered the remains of the eastern half of the Roman Empire, including “New Rome” Constantinople. And now, their seemingly unstoppable forces set their sights on conquering Rome, and from there, the rest of Europe and the New World.
Desperate for survival, Pope Pius V convinced as many Catholic rulers of the Mediterranean as possible to band together to stop the Ottomans, forming what they called the Holy League.
It was originally formed to save a Venetian colony on Cyprus that was under Ottoman attack, but the colony fell before they were able to arrive. The Ottoman commander captured the Venetian leader, had him flayed alive, and hung up his corpse along with the corpses of other Venetian leaders. So the Holy League sailed to meet the Ottoman navy at their naval station Lepanto in Greece instead.
The odds were against the Holy League: Despite the fact that many nations were banded together in the Holy League, the Ottoman forces still had more boats and were practiced in fighting together, rather than being cobbled together just for the occasion.
And the stakes were high: If the Holy League failed, the Ottoman’s would appear to have a cleared way to the heart of Europe in Rome.
Knowing that the circumstances were desperate, Pope Pius V did the only thing those back at home could do: pray. On the day of the battle, he organized a public procession in Rome to pray the Rosary.
And then a miracle happened: they received word that, against all odds, the Holy League had won! Overjoyed, and convinced that their prayers had been decisive, the Pope created the new Feast of Our Lady of Victory. A few years later, it was changed to the Feast of the Holy Rosary, and finally to the Feast of Our Lady of the Rosary in the 20th century, which it remains today. It is celebrated every October 7th.
Historians say that the battle truly was decisive in world history: it once and for all stopped the advance of Ottoman forces deeper into Europe, preserving the independence of the western half of Christendom.