Queen of Four Kingdoms

She and her husband actually ruled only parts of only two of their kingdoms (Naples and Aragon), and only during short periods. Their real realm was Anjou fiefdoms around France, which however were not kingdoms but duchies and other feudal lordships. They held the provinces of Provence and Anjou, also sometimes Bar, Le Maine, Touraine and Valois, and their son René became through his own marriage the lord of (Upper) Lorraine. In France, she was the duchess of Anjou and the countess of Provence. She preferred to hold court in Angers and Saumur. This Anjou "empire" was centered in Province, Southern France, which was located in relative middle of the extremes (South Italy, Western France, Aragon etc) of their possessions and claims. They supported the Avignon line of Popes (Antipopes) during the Western Schism - Avignon was located in their lands.

This Four Kingdoms were more a title than a real position of reigning king.

As consort of her husband, Louis II of Anjou, Yolande became in 1400, at their marriage, (titular) Queen of Sicily and Jerusalem. Sometimes Naples was also called a kingdom, and sometimes they exerted claims to kingdom of Cyprus. Her marriage to Louis II of Anjou in December 1400, at Arles or Montpellier (both have been mentioned), during her uncle Martin's reign in Aragon, was part of an effort, made also in earlier such marriages, to resolve the contested claims upon the kingdom of Sicily and Naples between the houses of Anjou and Aragon. Her husband Louis II of Anjou (d 1417) spent much of his life fighting in Italy for his claim to the realm of Naples, against the rival Angevin line, then represented by King Ladislas of Naples.

In 1410, Yolande´s uncle, king Martin I of Aragon, died without surviving issue. She had been regarded as heiress to her father, King John I of Aragon, even over Martin who however as closest male was recognized king in Aragon and Barcelona (and Yolande was underage when her father died and Martin ascended the throne), but during the lifetime of Martin she did not actively pursue her claims to Aragon. After Martin's death, however, there were no heirs of unbroken male line of Aragon-Barcelona. The country enjoyed (/endured) two years of interregnum, during which Yolande and her husband asserted Yolande's claim, and also succeeded in obtaining sometimes some parts of Aragon. Only momentarily they held parts of kingdom of Aragon, such as province of Roussillon near Pyrenees. Another claimant was the sons of Martin's and John's sister Eleanor (queen of Castile). In 1412, the Estates of Aragon elected second of those sons, Prince Ferdinand of Castile, as the next monarch of Aragon. Yolande and Louis did not accept that. They and their heirs claimed Aragon for a long time afterwards.

The title of Queen of Aragon was thus the fourth kingdom in the list of "Four Kingdoms" of Yolande and her Anjou family.

In 1442, they lost their last lands in any of these four kingdoms, when Yolande's son and heir René of Anjou was driven out of Italy (actually by the then rival Aragonese King, Alfonso V), where he until that had held some provinces of Naples. The title King (of these Four Kingdoms) remained in the family for a long time, until one Duke of Lorraine dropped it from his official titulary sometime during 16th century.

Their heirs were: eldest son Louis III of Anjou, d 1434, then their second son René of Anjou, d 1480, René's daughter Yolande, her son René II (duke of Lorraine), his son duke Anthony of Lorraine, and so forwards in the line of dukes of Lorraine.

In 1480 (death of René I), his brother´s son Charles however claimed the kingdoms (arguing that these kingdoms, or some of them, cannot inherited by a female, René's daughter Yolande. Charles IV (titular) king of Sicily died childless and willed his inheritance (including his claims to the kingdoms) to the then king of France, his cousin Louis XI. Louis's son Charles VIII of France actually succeeded in conquering Naples for a brief period.

Yolande of Aragon took an important role in the politics of the Mediterranean world, particularly France and Aragon, during the first half of 15th Century. In the Hundred Years' War, Yolande was the backbone of the French nationalists against the English and against the Burgundians. Charles VII of France's kingship and victory were largely results of Yolande's work. Yolande made her daughter Mary of Anjou marry Charles.