At the time of the Christian Reconquest of the Iberian peninsula, after the conquest of Lisbon (1147) by the forces of King D. Afonso Henriques (1112-1185), came to fall in the same year Sintra, Almada and Palmela. At the time, the Muslim forces that defended Palmela, abandoned it, taking refuge in Alcácer do Sal.
Thus, the Portuguese forces only mastered the village and its domains. The Muslim forces, however, soon reorganized, reviving the south bank of the river. Christians reconquered Palmela in 1158. Lost again shortly, it was finally conquered by the sovereign on June 24, 1165.
With the accession to the throne of King Sancho I (1185-1211), the village and its fields were donated, by the Sovereign, to the Military Order of Santiago, along with Almada and Alcacer do Sal (1186); by which time Palmela received its first charter, passed by his Master.
These locations would again fall before the onslaught of the forces under the command of the caliph Abu Yusuf Ya'qub al-Mansur, who, after having regained the Algarve, advanced to the north.
Only after the Battle of Navas de Tolosa (1212), in which there was a decisive victory for the Christians of the Peninsula, it was regained the lost lands beyond the borders stretching from the river Tagus to Évora.
D. Afonso III (1248-1279), on February 24, 1255, entrusted to the Order of Santiago, in the persons of his Master, D. Paio Peres Correia, the domain of the castle. His son and successor, D. Dinis (1279-1325), confirmed the Charter to the village (1323).
During the Siege of Lisbon by the Spaniards, was at the top of the towers of the Castle of Palmela, that Condestável D. Nuno Álvares Pereira, after the victory at the Battle of Atoleiros (1384), lit huge bonfires to warn the Master of Avis of his approach.
During his reign, D. João I (1385-1433) carried out work to expand and strengthen the castle (1423).
Later, in the context of the War of the Spanish Succession, D. Pedro II (1667-1706) determined to modernize the defenses of the castle, which received bastion lines, adapting it to the artillery fire.
In the eighteenth century, the structure of the castle was badly damaged by the earthquake of 1755. Even so, it remained occupied by the friars of Palmela until 1834, with the extinction of religious orders in Portugal. It was then occupied by a contingent of the Portuguese Army.
It was declared as a National Monument on June 23, 1910.
The facilities of the former convent were reclassified in 1945 as a hotel, integrating, from the 1970s, the Pousadas of Portugal.
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