Saint Juan Diego was canonized by Pope John Paul II on July 31, 2002 in Mexico. Juan Diego was the indigenous Catholic layman to whom Our Lady of Guadalupe appeared in 1531. Before this time, European missionaries had not seen many conversions of indigenous people to Catholicism. After our Blessed Mother appeared as a brown-skinned Aztec princess, Christianity began to spread rapidly. Saint Juan Diego became the messenger of Our Lady taking the Gospel to the Americas. He dedicated the rest of his life to prayer and served in the church that was built in honor of the Virgin.
All of this occurred before European colonies were established in what became the United States. For this reason, Our Lady of Guadalupe is known as "Our Lady of the Americas."
The feast day of Saint Juan Diego is December 9, the day he witnessed the apparition of Our Lady of Guadalupe.