- Another significant siege during the 1383-1385 dynastic crisis.
- Almada, town on the southern margin of the Tagus, across from Lisbon, also suffered a long siege surrounded by Castilian forces.
- The Master of Avis was able to communicate with those inside faithful to him through a messenger who managed to swimm across the river six times. Finally, realizing the extreme suffering of the population and the number of dead, including children, the Master of Avis advised the governor to negotiate the handing over of the castle to the King of Castile. At first, Juan of Castile, kept the Master's messenger waiting, in order to inflict further suffering to the besieged. His wife, however, Queen Beatriz, daughter of Fernando of Portugal, entreated him to accept the castle, which he finally did, including the safeguard of its inhabitants and their belongings. [João1, ch. 137: 23-56]
- At present, there is an on-going debate on whether gunpowder was used during this siege. Professor Teresa Amado, however, maintained that gunpowder had not been used in Portugal before the Battle of Aljubarrota, in August 1385.
Not to Scale