So, why is Mary venerated more widely than any other woman?
Power lists of remarkable women are frequently compiled and we all enjoy considering the names of the most influential women in the world: Angela Merkel, Hillary Clinton, Aung San Suu Kyi, Christine Lagarde.
Yet, surprisingly, the scientific and usually secularist magazine National Geographic has nominated its Most Powerful Woman in the World for December 2015 as Mary, the mother of Jesus Christ, who, it claims, is venerated more widely than any other single female.
A satellite map showing world locations where visions of Mary have been seen, or claimed, is dotted with markers - from North and South America to Africa to Russia to China to Europe.
The Blessed Virgin Mary is described as an international power of many designations - Our Lady of Siluva (Lithuania), Our Lady Help of Christians (Czech Republic), Our Lady of Happy Meetings (Alpine France), Our Lady of Zion (Naples), the Virgin with the Golden Heart (Belgium), Our Lady of Zaytun (Egypt), Mother of the Word (Rwanda) and Our Lady of Good Success (Ecuador) being among the multiple places associated with the BVM.
And that's besides the more famous Lourdes, Fatima, Medjugorje and, in Mexico, Our Lady of Guadaloupe.
Guadaloupe, which dates from 1531, when Mary revealed herself to an Indian man, Juan Diego, is said to be central to Mexican identity.
I'm glad to see that Our Lady of the Miraculous Medal in Paris is honoured as an especially successful shrine. This chapel, located in the Rue du Bac, is an exquisite confection of femininity - all blue stars and gold gossamer and attracting women of many nations.
My mother was especially fond of the Rue du Bac, because of its beauty and history (dating from 1830, when St Catherine Laboure had a vision of the BVM here). And the proximity of the grand magasins - the famous Parisian department stores of Galeries Lafayette and Au Printemps - was nice.
The BVM is surely "a global phenomenon", as the National Geographic writer Maureen Orth notes. Mary has been a significant figure since 431 AD, at the Council at Ephesus, when she was officially named 'Theotokos - Bearer of God'.
Throughout the centuries, her presence has been ubiquitous, though the image has also changed with the spirit of the age - more imperialist in the first millennium of Christianity, when she was seen as a kind of Empress, adorned in purple and gold; in more recent centuries, an image of compassion, pity for suffering humanity, fortitude, and especially the trials of motherhood.
The museum at Knock bears witness to the way in which the BVM was a source of consolation to mothers through decades of hard times. And it's evident that Mary is a source of power, help and consolation to many millions (in Egypt a Marian festival draws two million worshippers); and many have claimed healing from illness, both physical and mental, through the BVM.
Yet growing up in a Marian culture - as Ireland was in my childhood - I would say that many of us also rebelled against the cult of the BVM. She seemed to represent a certain passivity in women - she didn't initiate anything, she accepted.
She seldom spoke - she kept her thoughts within her heart. Attitudes reached the absurd when the nuns told us that "Our Lady blushed" at the slightest sign of "immodesty" (crossing your legs, thus showing your undies). Learning about the woes, cruelty, oppressions, injustices, and general horrors that obtained in the world, it might seem that Our Lady had rather more to upset her.
Significantly, contemporary visionaries, from Rwanda to Medjugorje, now emphasise that aspect of Mary's message: that she calls for peace, for prayer, for repentance, for reconciliation, rather than the aggressions that stalk humanity.
It's impressive that so many peoples, so many cultures, feel a sense of presence about the BVM, and that her sovereignty is acknowledged with such a global reach: she is often called 'Queen' (of Patriarchs, of Angels, of Prophets, of Apostles, of Martyrs, of Peace).
The cult of Mary is also worth billions of dollars, which is another measure of power, although billions of dollars can also be a source of exploitation.
The Reformation, starting with Martin Luther in 1517, came to regard the cult of Mary as verging on the pagan, and Evangelical Protestants remain a little cool about the BVM, but Marian devotion always returns one way or another.
And Mary is mentioned more often in the Koran than in the New Testament. 'Maryam' is venerated by Muslims as the mother of Jesus, and "holy above all women". Perhaps this could be a route towards peaceful dialogue someday?
Does the BVM perform miracles? Science has, apparently, no satisfactory explanation for miracles claimed, and visions of Mary generally seem sincere. (Michael O'Neill of Stanford University has codified every apparition of Mary since 40 AD, for his website miraclehunter.com).
Most powerful of all women? Yet maybe the most poignant image of Mary remains that of a teenage pregnant girl on a donkey, travelling towards Jerusalem to give birth in a manger.