But, following its alignment with the Kingdom of Castile during the 1383–1385 Portuguese interregnum, the site began to fall into disorder. According to the chronicler Fernão Lopes, Monsanto was a village that had been loyal to Queen Beatrice. But, later however, Lopes listed the town among those aligned themselves with D. John by 1384. Beginning in the 1476, the area was reconstructed during the reign of King D. John I, resulting in the construction of a barbican and protection over the well, a large chamber that belonged to the Castro family (later identified as providing abundant water for the site). By 1496, the "Inquirição" indicated 309 inhabitants.