the throne, with grave consequences to herself (Leonora), hated as she was by the Portuguese people. Leonor persuaded her brother João Afonso Telo 6th Count of Barcelos and Alcaide-Mór (noble magistrate) of Lisbon, to insinuate the idea in the mind of the Infante that his marriage to her daughter, the heiress presumptive Beatrice (who was promised to John I of Castile), would find favour with the people and clear his way to the throne. With the false imputation that his present wife María had been unfaithful to him, transmitted by Leonora through John Alfonso, Infante John became so enraged that he stabbed María in Coimbra. In one single coup, Leonor Teles got disentangled of her sister and brought such opprobrium upon the name of her brother-in-law, that his hopes of succeeding to the throne were much diminished. Having committed this crime of passion, John fled to Beira. Ferdinand I intended, or pretended he would, to punish the culprit, but he was soon forgiven and returned to his place in the royal court. When he spoke, however, of marrying his half-niece, the Infanta Beatrice, the Queen herself disillusioned him. Infante John, realizing he had been ensnared by the machinations of Leonora, retired to the Douro and then to Castile, avoiding the persecution that was encouraged by the cunning Leonor. Henry II called Infante John to his court and gave him in marriage his illegitimate daughter Constance of Castile, in about 1378. When the Castilian army invaded Portugal, John joined its ranks and laid siege to Elvas, which held firm. Upon the death of Ferdinand I, John I of Castile had him arrested, considering him a threat as the most direct successor to the Portuguese throne. Meanwhile, his connections with Castile eventually cost him the throne, thanks to the argumentation of Master João das Regras at the Cortes of Coimbra in 1385. During the Battle of Aljubarrota he was already out of the country like his brother Denis, both of them having left Portugal for Castile, although during the 1383–85 crisis he was one of the claimants to the throne, along with Beatrice of Portugal (his half-niece), John, Master of Aviz (his half-brother) and Denís (his brother). Shortly after the battle of Aljubarrota, John was released. He and his new wife were created lord and lady of Alba de Tormes in 1385 by the King of Castile (his brother-in-law). In the summer