Pedro the Cruel (1334-69), King of Castile and Leon, was the son of Alfonso XI., whom he succeeded in 1350. He received his. surname in consequence of the murder of his brother, Don . Fadrique (1358), who had joined the fallen minister, Albuquerque, and another brother, Don Enrique, in stirring up a revolution. Enrique fled to France, but returned in 1366 with an army composed of free companies, led by Bertrand du Guesclin and Calverley. Pedro then secured the aid of Edward the Black Prince, by whose forces Enrique was defeated in the battle of Najera or Navarrete (April, 1367); but he failed to fulfil his promises to the prince, and alienated him by his haughty conduct. Edward, therefore, returned to France, and in 1369 Pedro was vanquished by Enrique at Montiel. A few days later he was inveigled into visiting his brother in his tent, and there a quarrel broke out, in which Pedro Was slain.