A deluge of graces came after the consecration to Our Lady of the Assumption

After French King Louis XIII managed to quell a Protestant rebellion in La Rochelle in 1628, and built the Church of Our Lady of Victories in Paris in thanksgiving, the next year he and the Queen were able to conceive a child, after 20 years of sterility. The king then decided to make an official vow to solemnly entrust France to the Virgin Mary:

"So many evident graces have been received that we do not want to differ our gratitude or to wait for a peace which will come from the same hand who issued them and which we desire ardently, to share its fruits with the peoples we are committed to serve… We declare that, taking the very holy and glorious Virgin Mary as special protectress of our kingdom, we particularly consecrate to her our own Self, the State, our Crown and our subjects."

This vow was published as a royal edict recorded by the Parliament and has force of law. The "always victorious" King had officially dedicated France to Mary, on February 10, 1638. He also established the feast of Assumption, on August 15th, as a new national holiday.

As Father René Laurentin wrote in his 1988 study for the 350th anniversary of the Vow of Louis XIII, contemporaries were amazed at the joy of the people and the great expression of thanksgiving everywhere, following this vow: "Never has a people, on any occasion, shown more joy. It is a great and sure proof of the love that these subjects have for their king, when they welcome with such transports the prospect of being one day governed by his posterity," wrote Grotius, ambassador of Protestant Sweden, in 1638.

Excerpts from Marie et la France, un lien extraordinaire à redécouvrir, Editions MDN Productions, Paris, June 2019