Claims and Counterclaims to Other Thrones
There were many claims on various noble titles as a result of all those noble children marrying each other over the years. Some of the claims were quite strong, and several quite interesting.
Teodoro Paleologo (251) of Montferrat had a claim on the Byzantine Empire. He was the second son of Yolando-Irene, the daughter of the Marquis of Montferrat, and the Emperor Andronikos II. When his mother's brother died without issue in 1305, his mother resigned the marquisate to him, perferring to remain with her other husband. So the 15-year old Teodoro (Theodore) headed West. Meanwhile, Teodoro's older brother died, and in 1328 his nephew, became emperor as Andronikos III. Should something happen to Andronikos, Teodoro (the emperors uncle) might be considered an emperor in waiting. The emperor also has the count of Savoy as a father in law.
Giovanna d'Anjou (NPC 445), is the heiress to Robert of Anjou (231). Although the Salic Law prohibited her from actually inheriting Arles, she can have Naples, and also has a claim on the Byzntine throne, as heiress to the Latin Emperor of Constantinople, a distinction shared with some cousins who are not in play. Giovanna was also related to Edward III of England. This can be seen by tracing the male line of the Counts of Anjou back to Geoffrey II of Chateau-Landon, Count of Gatinais who married Ermengarde, the heiress of Anjou around the first quarter of the 11th Century. Geoffrey and Ermengarde's grandson, Count Fulk V, resigned Anjou and Maine (the latter acquired through his first marriage) to his eldest son Geoffrey and went off to the Crusades. Geoffrey, the son who stayed at home to rule Anjou and Maine acquired the nickname Plantagenet from the sprig of the broom plant which he jauntily wore in his cap. It was he who married Henry I's daughter the Empress Matilda and became the ancestor of the Planatagenet kings, their son being the famous Henry II (as in the films Beckett and The Lion in Winer). However the name Plantagenet was not used by Geoffrey's descendants until around 1448 when Richard, Duke of York, revived it to emphasize the superiority of his claim over that of the house of Lancaster. So the Plantagenets and d'Anjou's are of the same family. All the others since the 11th century who have broken off from this family are all are related thru various ways.
Leon d'Anjou (170) is technically King of Armenia and Cyprus.
There is also a titular King of Jerusalem running around.