JOANNA II. (1371-1435), queen of Naples, was descended from Charles II. of Anjou through his son John of Durazzo. She had been married to William, son of Leopold III. of Austria, and at the death of her brother King Ladislaus in 1414 she succeeded to the Neapolitan crown. Although now a widow of forty-five, she chose as her lover Pandolfo Alopo, a youth of twenty-six, whom she made seneschal of the kingdom. He and the constable Muzio Attendolo Sforza completely dominated her, and the barons determined to provide her with a husband who would break her favourites and yet not make himself king. The choice fell on James of Bourbon. James at once declared himself king, had Alopo killed and Sforza imprisoned, and kept his wife in a state of semi-confinement ; this led to a counter-agitation on the part of the barons, who forced James to liberate Sforza, renounce his kingship, and eventually to quit the country. The queen now sent Sforza to re-establish her authority in Rome, whence the Neapoli tans had been expelled after the death of Ladislaus ; Sforza en tered the city and obliged the condottiere Braccio da Montone, who was defending it in the pope's name, to depart (1416).
But when Oddo Colonna was elected pope as Martin V., he allied himself with Joanna, who promised to give up Rome, while Sforza returned to Naples. The queen was, however, completely dominated by her new lover Giovanni (Sergianni) Caracciolo.
Sforza then favoured the pretensions of Louis III. of Anjou to Naples as Joanna's successor. Joanna refused to adopt Louis as her heir, and appealed to Alfonso of Aragon, promising to make him her heir. War broke out between Joanna and the Aragonese on one side and Louis and Sforza, supported by the pope, on the other. After much fighting by land and sea, Alfonso entered Naples, and in 1422 peace was made, But dissensions broke out between the Aragonese and Catalans and the Neapolitans, and Alfonso had Caracciolo arrested; whereupon Joanna, fearing for her own safety, invoked the aid of Sforza, who with difficulty carried her off to Aversa. There she was joined by Louis whom she now adopted as her successor. Sforza was accidentally drowned, but when Alfonso returned to Spain, leaving only a small force in Naples, the Angevins with the help of a Genoese fleet recaptured the city. For a few years there was peace in the kingdom, but in 1432 Caracciolo, having quarrelled with the queen, was seized and murdered by his enemies. Internal dis orders broke out, and Gian Antonio Orsini, prince of Taranto, led a revolt against Joanna in Apulia; Louis of Anjou died while conducting a campaign against the rebels (1434), and Joanna herself died on Feb. II, 1435, after having appointed his son Rene her successor.