We read that St. Vicente Ferrer was in Salamanca at the beginning of the fifteenth century, and as a Spanish writer has it, converted the Jews to the unity of the faith on the ruins of their synagogue. He does not appear to have been equally successful in converting the Christians to the spirit of their faith, to judge from the following tragic incident which stained the history of Salamanca in his day. A quarrel arose over a game of pelota between two brothers of the family of Manzano and two of the Enriquez. The two latter were slain, and their slayers fled to Portugal. The mother of the victims, Doña Maria Rodriguez de Monroy, shed no tears, but silently and stoically gathered together her retainers and retired to her country seat at Villalba. A day or two later she, with a few followers, suddenly fell upon the murderers of her sons as they sat in fancied security at their inn in some Portuguese town, killed them, and bore their heads in triumph back to Salamanca, where she flung them upon the tombs of the Enriquez. But from this deed of vengeance sprang a bloody vendetta between the two families and their partisans, which the eloquence of St. Juan de Sahagun in 1460 allayed but could not extinguish. When forced to lay aside the sword and dagger, the bowl and philtre became the instruments of this unquenchable hate. Nay, as late as the reign of Philip II., the rival factions wore different colours, and eagerly seized the opportunity to contend against each other in jousts and tournaments. Juan de Sahagun, whose good deeds are strikingly relieved against so dark a background, himself fell a victim to poison, administered by a lady, whom his preaching and exhortations had deprived of her lover. Acclaimed at once (1479) as the patron of the city, it was not till October 17, 1690, that he was formally enrolled in the list of the saints of the Catholic Church. His feast is celebrated on the day of his death (June 11). The fierce passions of the Salamancans were inflamed throughout the fifteenth century not only by private but political animosities. In the reign of Juan II. the city was alternately the prey of the partisans and the opponents of the royal favourite, Alvaro de Luna. When the king visited the town in 1440, the Archdeacon Juan Gómez, son of the late bishop, Don Diego de Anaya, a furious adversary of the Constable, garrisoned the alcazar of San Juan and the tower of the cathedral, and compelled his sovereign to take refuge in the house of one Acevedo. The fortress was again garrisoned against the king (Enrique IV.) six years later by Pedro de Gutiveros, but this time the bishop was on the royal side, and, with the help of Suero de Solis, expelled the rebel from the town. In gratitude for this and his friendly reception by the citizens in 1465, the unfortunate king ordered a fair or open market to be held every year from the 8th to the 21st of September, and to the delight of the townsmen decreed the demolition of the alcazar.