Cross-border relations: the frontier of war (I)

Once the Reconquest finished (1492) and the Muslims had been expelled from the Iberian Peninsula, the Castilians found it was impossible to annex the Kingdom of Portugal, so they stigmatised the Portuguese as a kind of new heretics. The Muslim «other» was replaced by the Portuguese «other», the neighbour became the enemy, opposition escalated, new quarrels broke out and a string of new and remodelled fortifications sprung up along the border.