In 1372, when King Fernando married Dona Leonor, King Enrique was in Burgos. There he learned that a number of knights and squires from Castile, who were living in Portugal, namely Fernando de Zamora and others, had captured Viana, a Galician town located in his kingdom, and were waging war against him from there. Similarly, sailors from the coasts of Vizcaya and Asturias informed him that King Fernando had ordered the capture of a number of his naos, both at sea and in the port of Lisbon, but they did not know why. He was also informed that King Fernando was forming an alliance with the English, with a view to their jointly invading his kingdom and waging war on him.

King Enrique was greatly aggrieved at this news, because he had a peace treaty with King Fernando, yet King Fernando by these actions was giving the impression that he had no intention whatever of keeping that treaty, both by permitting the Castilian knights who were based in his kingdom to wage war on him and by ordering the capture of his naos for no reason. In order to ascertain whether the King of Portugal intended to maintain the friendly relations and alliance which King Enrique had with him, he sent to him Diogo Lopes Pacheco, who at this time was living in Castile and had constantly been with King Enrique ever since he had fled Portugal because of the death of Dona Inês.

Diogo Lopes arrived in Portugal, told King Fernando everything that King Enrique had commanded him to say and received a reply from him. When he went to speak with Prince Dinis, the prince told him of the marriage of the king, his brother, adding how troubled he was at the way in which the king had gone about it and how at odds he was with the king owing to his refusal to kiss the queen's hand.

Diogo Lopes replied that he had spoken to the king and was concerned at how he had appeared to him, because it seemed to him that the king was wholly in the power of Queen Leonor and that it was as though she had bewitched him, since he did only what she wanted. The prince asked him for his opinion on these circumstances.