Bl. Alanus de Rupe (Alan de la Roche, c. 1428–1475) was a Breton Dominican who began an aggressive preaching campaign for the Rosary across Flanders, France, and the Rhineland in the late 1460s. He claimed personal revelations from St. Dominic and the Blessed Virgin Mary directing him to restore the Rosary as a great pillar of Catholic devotion (it had been preached by St. Dominic in the 13th century but had fallen into general neglect by the 15th).
On September 8, 1470, the feast of the Nativity of Mary, Alanus founded the first Confraternity of the Most Holy Rosary at the Dominican priory of Douai. Within thirty years, similar confraternities had been founded in Cologne, Frankfurt, Venice, and Rome, with several millions of members. The 'Fifteen Promises of Mary to those who pray the Rosary' — codified by Alanus — became one of the most-printed devotional documents of the early modern period. Alanus is venerated as Blessed; the Confraternity of the Most Holy Rosary remains the principal Rosary lay-confraternity of the Catholic Church.