Río Miño
Aside of this political division of interests, it was during this time period that the Galician-Portuguese language became a reality and subsequently evidenced the common cultural and linguistic heritage that both kingdoms still shared. Their vernacular language became one of the most important lyrical and literary languages of Europe and was taken in great regard by the neighboring Castilian royal court. Among the conjointly claimed literary production written on any of both sides of the Minho River there is the "Cantigas de Santa Maria", the Martín Codax's "Pergaminho Vindel" or the "Cancioneiro da Ajuda".