The English victory was complete. At noon the battle was over, and the Black Prince ordered his banner to be fixed in a bush on a little height, as a rallying-point for his men on their return from the pursuit. The Duke of Lancaster and others among the knights did the same, and the men soon gathered round the different banners in good order. The Prince bade that they should look among the dead for the body of Henry of Trastamare, and also discover what men of rank had been slain. He then descended, with Don Pedro and his knights, to King Henry's lodgings. Here they found plenty of every sort, at which they rejoiced greatly; for they had suffered great want before. When the men returned from searching the battle-field, Don Pedro was much displeased at hearing that his brother was not among the slain. The slaughter had been very great amongst the common soldiers. Besides those lying dead on the battle-field, many were drowned in the river.
That night the army rested in ease and luxury, enjoying plenty of food and wine. Next morning, which was Palm Sunday, Pedro's mind was already full of thoughts of revenge. He came to the Prince, and asked that he would give up to him all the Spanish prisoners, the traitors of his country, that he might cut off their heads. But the Prince answered him—"Sir King, I entreat and beg of you to pardon all the ill which your rebellious subjects have done against you. Thus you will do an act of kindness and generosity, and will remain in peace in your kingdom." Pedro was not in a position to refuse the Prince's request, since he owed everything to him, and he had to pardon all the Spanish nobles, excepting one, who in some manner had earned his special anger, and whom the Prince gave up to him. He was beheaded in front of Don Pedro's tent, before his very eyes.
The next day the army set out on its march toward Burgos, and the citizens, who knew that resistance was useless, opened their gates to Don Pedro. The Prince and his army encamped in the plain outside the town, as there were not comfortable quarters for them all inside. Here the return of Don Pedro was celebrated with tournaments, banquets, and processions; and the Black Prince presided as judge over all the tournaments. All Castile yielded to Don Pedro, and the Black Prince might congratulate himself that he had done his work speedily and well. He exhorted Pedro on every occasion to treat his people well, and pardon their revolt from his rule, saying to him, "I advise you for your good, if you would be King of Castile, that you send forth word that you have consented to give pardon to all those who have been against you." Pedro promised everything he asked; and as long as the Black Prince stayed by his side, he did not dare to indulge his desire for vengeance.
But when the Prince had been a month at Burgos, he began to be impatient to return to his own dominions. He had as yet received none of the promised money from Pedro, in payment of the expenses of the campaign. He therefore told the King that he was anxious to return and disband his army, and demanded the money to pay his troops. Pedro said that he fully intended to pay as he had promised, but that at that moment he had no money. At Seville, however, he had a large treasure, and if the Black Prince would allow him to depart, he would go and fetch it. Meanwhile, he proposed that the Prince and his army should quarter themselves in the fertile country round Valladolid. He promised to bring him the money at Whitsuntide. The Black Prince, himself always honest and straightforward, was ever ready to trust in others, and easily agreed to do as Pedro proposed. It was a fatal step; for once away from Pedro's side, he lost all hold upon him.
The Prince's army established itself round Valladolid, and the Free Companies supported themselves by pillaging the peasants. The summer drew on, and the army began to suffer from the hot climate. Disease broke out in the camp, and it is said that four out of every five of the soldiers died. Whitsuntide came, but brought no money from Pedro. The Prince grew more and more uneasy. At last he sent three of his knights to the Spanish King, to ask him why he did not keep his promise. To them Pedro professed great sorrow that he had not been able to send the money sooner, and repeated his promises; but said that he could not drain his people of money, and, above all, he could not send any money as long as the Free Companies were in the country; for they did so much harm. If the Prince would send the companies away, and only let some of his knights remain, he would soon send the money. When this answer was brought back to the Prince he became very sad; for he saw clearly that Don Pedro did not mean to keep his promises. His own health was failing; he had been attacked by an illness which was never to leave him. Bad news was brought him from Bordeaux. The Princess wrote that Henry of Trastamare was attacking the frontiers of Aquitaine. His army was rapidly dwindling before his eyes. Man after man died from the effects of the climate. There was nothing for it but to return to Bordeaux. In sadness he gathered his troops together, and felt thankful that he was allowed to pass peaceably through Navarre and the dangerous passes of the Pyrenees.
At Bayonne he disbanded his army, now only a miserable remnant of the magnificent array of troops which he had led into Spain. He bade them come to Bordeaux to receive the payment due to them. He said to them, that though Don Pedro had not kept his engagements, it did not become him to act in like manner to those who had served him so well. On his arrival at Bordeaux he was received with solemn processions, the priests coming out to meet him, bearing crosses. The Princess followed, with her eldest son Edward, then three years old, surrounded by her ladies and knights. They were full of joy at meeting one another again, and embraced most tenderly, and then walked together hand in hand to their abode. Soon after the Prince assembled all the nobles of Aquitaine, who had joined in this expedition, thanked them heartily for their help, and distributed among them rich presents of gold and silver, and jewels.