In the high Middle Ages, the village was castellated, and one of the first restocking was due to Afonso III of Asturias, who conquered the fortress from the Moors.

The first Charter that S. João da Pesqueira received dates back to the reign of Fernando "O Magno", between 1055 and 1065, being, in this way, one of the oldest in the country. Later, other monarchs granted charters or confirmations, namely D. Afonso Henriques still Infante, in 1110, D. Sancho I in 1198, D. Fernando in 1376 and during the reorganization of the municipalities undertaken by D. Manuel I, in 1510.