The cult of Our Lady continued to grow, justifying works on the original chapel around 1431, curiously the year in which Joan of Arc was burned at the stake in France and, in Portugal, Dom Nuno Álvares Pereira, known as the Saint Constable, died. At that time, the bishop of Évora, Dom Pedro de Noronha, had already obtained permission from the Pope (in 1422) to found a monastery there. However, the monastery was only founded in 1457 with papal authorization, and its observance was handed over to the Order of St. Jerome. The convent, that is, the religious community, was established on September 2, 1458, with twelve friars; by then, the work on the monastery, that is, the physical structure, had already been completed. Weeks before, Pope Callixtus III had died, to whom we owe the bull Pia Deo founding Espinheiro and who was the pope who recognized the innocence of Joan of Arc (who had been burned as a witch in 1431).

The last campaign of works was in 1801, as stated on the plaque below the choir. The French arrived in 1808 and in 1834 the Religious Orders were abolished in Portugal. The monastery was then sold to private individuals and transformed into a farmhouse. However, the church, classified as a national monument since 1910, maintained its public cultural vocation, where many faithful and pilgrims continued to flock throughout the 20th century, especially for the annual festival celebrated on Ascension Thursday.