King Alfosno XI, who visited the chapel more than once, invoked Santa Maria de Guadalupe in the Battle of Rio Salado. After gaining the victory, he ascribed it to the Madonna's intercession, declared the church at Guadalupe a royal sanctuary and undertook an extensive rebuilding program.
The monastery is rich in associations with the New World, where Our Lady of Guadalupe is highly revered in the Mexican Basilica of Guadalupe and elsewhere. It was here, in Extremadura, that Christopher Columbus made his first pilgrimage after discovering America in 1492 and it was here that he first thanked heaven for his discovery.
Even after the monks from Guadalupe founded the famous monastery of Escorial, which was much closer to the royal capital, Madrid, Santa Maria de Guadalupe retained the royal patronage. It remained the most important cloister in Spain until the secularization of monasteries in 1835. In the 20th century, the monastery was revived by the Franciscan Order and Pope Pius XII declared the shrine a "Minor Papal Basilica" in 1955." - in: wikipedia