Sunday, May 13, 1917 would prove to be an auspicious day, both for the Catholic Church and for the whole tumultuous course of the 20th century. In the Sistine Chapel, Pope Benedict XV consecrated Eugenio Pacelli as archbishop, prior to sending him off to be nuncio to Bavaria. Thus one pope, an indefatigable voice for peace throughout a war then engulfing the world, sent off another on his path – as the future Pope Pius XII – to play a pivotal role in the next.

As unlikely as it sounds, 1,100 miles away on a dusty Portuguese hillside, something of perhaps greater import was taking place. Three primary-school age children – siblings Francisco (aged nine) and Jacinta (seven) and their cousin Lucia (10) – were tending their families’ sheep. Startled by a sudden burst of light, they looked up expecting to see a thunderstorm coming. Instead, before them, as Lucia would later recount in her memoirs, was “a lady, clothed in white, brighter than the sun”.

So began a remarkable series of apparitions at Fatima, an out-of-the-way village 80 or so miles north of Lisbon. Or rather, so they continued: this Lady in White was not the first visitor “from heaven” (as she told them) to have appeared “while shepherds watched”. The year before, for example, a figure calling himself “the Angel of Peace” had spoken to the children several times.

This latest visitation, however, marked a new and significant phase. As the Lady informed them: “I have come to ask you to come here for six months in succession, on the 13th day, at this same hour. Later on, I will tell you who I am and what I want.”

A great deal happened in those six months, very little of which may be recounted here. Each 13th day, however, the Lady returned as promised. Alongside her repeated appeals for penance, prayer and fasting, she entrusted the children with three revelations. Together, these made up the so-called Secret of Fatima.It is here where traditional Catholic piety and the “private revelations” of mystics enter the global stage of geopolitics.

On July 13, “Our Lady of the Rosary” (as she identified herself) entrusted the children with the first two parts of the secret. The first, and most important, we will deal with later. In the second, however, she warned them that unless the world repented, and sharpish, then not only would the current war continue, but it would soon be followed by a second and much worse one. This would be heralded by a “Great Sign” in the sky (in retrospect, often identified as the great Aurora Borealis of January 1938). To prevent this, Our Lady asked that Russia be consecrated to her Immaculate Heart, and the First Saturdays Devotion be begun in reparation.

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