St. Juan Diego, a humble Aztec peasant, saw the Blessed Virgin Mary on the Hill of Tepeyac near present-day Mexico City on December 9, 1531, the feast of the Immaculate Conception at the time. After a request by the bishop to prove her identity, Our Lady asked Juan Diego to gather the roses which he found growing on the hill, which were neither native to the area nor in season, and take them to the bishop. Juan Diego did so and placed the roses in his tilma (or cloak). Upon opening the tilma to reveal the miraculous roses to the bishop, there was something even more miraculous present—an image of the Virgin Mary dressed as a pregnant Aztec princess. The various design elements on the tilma read like a codex to the Aztecs, revealing to them the truth of the Catholic faith preached by the missionary priests.
Millions quickly converted to the Catholic Church as a result. This apparition and image is venerated under the title of Our Lady of Guadalupe, the first Marian apparition in the New World, and the only one where Our Lady produced an image of herself. The perfectly preserved tilma is venerated at her basilica and shrine in Mexico City.
Our Lady of Guadalupe is the patroness of the Americas, the New Evangelization, and unborn children. Her feast day is December 12th.