The Santa Clara buildings were originally built by King Alfonso XI as his palace in 1344. His son Peter the Cruel had it embellished by Mudéjar artists, beautiful works at Santa Clara, though on a much smaller scale than they did in the Alcázar of Seville. The facade, a lovely small patio, a chapel and the baths remain of Peter the Cruel's palace. Blanche de Bourbon was held here after her abandonment by Peter for María de Padilla in 1353. The former portal, blocked off now, has a particularly fine Mudéjar doorway. In 1363 he ceded Santa Clara to two of his daughters by María de Padilla. They turned it into a convent, but it retained its role as a royal palace.
Santa Clara convent's saddest association is with Joanna I Queen of Castile and Aragon, the daughter of Isabella I of Castile and Ferdinand II of Aragon, widow of Philip I of Castile and mother of his six children including Charles V, Holy Roman Emperor - popularly known as Juana la loca (Joanna the mad) - who was confined here for almost half a century until her death in 1555.
References:Trenčín Castle is relatively large renovated castle, towering on a steep limestone cliff directly above the city of Trenčín. It is a dominant feature not only of Trenčín, but also of the entire Považie region. The castle is a national monument.
History of the castle cliff dates back to the Roman Empire, what is proved by the inscription on the castle cliff proclaiming the victory of Roman legion against Germans in the year 179.
Today’s castle was probably built on the hill-fort. The first proven building on the hill was the Great Moravian rotunda from the 9th century and later there was a stone residential tower, which served to protect the Kingdom of Hungary and the western border. In the late 13th century the castle became a property of Palatine Matúš Csák, who became Mr. of Váh and Tatras.
Matúš Csák of Trenčín built a tower, still known as Matthew’s, which is a dominant determinant of the whole building.