In 1471-1472 Ferrante King of Naples (r. 1458-1494) ushered in an ambitious political program with clear imperial overtones. This project was centered (at least initially) on countering the Ottoman advance and was based on a complex system of marriage alliances set up through Ferrante’s numerous legitimate and illegitimate children as well as his nieces. This paper shows how Ferrante used his nieces, the daughters born of his sister Eleonora and the disgraced baron Marino Marzano, to draw in a select group of magnates from the eastern, “Illyrian” coast of the Adriatic. These were magnates with previous connections to the Aragonese regime that had been established by Ferrante’s father, Alfonso King of Aragon and Naples (r. 1416/1442-1458). However, after the Ottoman conquest of Bosnia in 1463, they found themselves in a desperate state, as they came under pressure not only from Ottoman raids but also from the centralizing politics of their overlords. Vlatko Kosača, Duke of St. Sava, an Ottoman tributary; Count Stjepan Frankapan of Modruš, a subject of the King of Hungary; and Count Ivan Frankapan of Krk, a Venetian vassal. This paper examines the political circumstances that drove these magnates to respond to Ferrante’s calls and traces the dynamic of the marriage negotiations that transpired between them. The marriage negotiations of Vlatko Kosača are by far the best attested of the three and seem to have been carried out with the least obstacles. Drawing on previously unpublished or simply unknown sources (published in Appendix 1), this paper reconstructs the complex three-way communication that transpired from December of 1472 till June of 1473 between the Neapolitan court, Duke Vlatko in (Herceg-)Novi, and, finally, Vlatko’s sister Catherine, the exiled Queen of Bosnia, who, together with Nicholas bishop of Modruš, helped broker the deal from Rome. The result was the marriage of Duke Vlatko and Ferrante’s niece Margherita Marzano, celebrated in May of 1474. Ivan Frankapan of Krk and Stjepan Frankapan of Modruš established direct contacts with the Neapolitan court as early as October of 1472, when an unnamed Neapolitan envoy — perhaps Ferrante’s resident ambassador in Venice, Anello Arcamone — arrived in Croatia as part of the joint Venetian-papal-Neapolitan mission to reconcile the Croatian magnates (extensive documents related to which are published in Appendix 2). It is argued, however, that both the Frankapani of Krk and the Frankapani of Modruš, much like Costanzo Sforza of Pesaro, were first presented with an opportunity to marry Ferrante’s nieces at the wedding of Ferrante’s older daughter Eleonora d’Aragona and Duke Ercole d’Este in Ferrara in July 1473, which tellingly they both attended. Their experiences with the Neapolitan court thereafter were quite different, as revealed, among other things, by new archival evidence regarding their contacts with Italian courts (the most extensive of which are published in Appendix 3). Ivan Frankapan thus seems to have begun the discussions regarding the marriage of his son Nikola with a Neapolitan princess at the end of 1473 or in the first half of 1474, making use of the growing Neapolitan-Venetian enmity over Cyprus. His plan of secretly sending his son to the Neapolitan court was, however, foiled by Venice, as was his subsequent plan to marry him off to the daughter of Ferrante’s captain general, Federico da Montefeltro. Stjepan Frankapan, on the other hand, had a tense relationship with his overlord, King Matthias of Hungary, but, though he constantly maintained independent contacts with the Italian courts, he only responded to Ferrante’s proposal after September 1474, when the Neapolitan-Hungarian marriage alliance was agreed. The result was the marriage of Stjepan’s son Bernardin to Luisa Marzano, which was celebrated in Naples in summer of 1476, just before the per procuram marriage of Beatrice d’Aragona and King Matthias. This marriage, finally, after a decade of tense relations, brought the Frankapani of Modruš back into their king’s grace. Ultimately all three lords turned to King Ferrante for political reasons and all three hoped that marriages to his nieces would also be followed by the establishments of Aragonese bridgeheads on the eastern Adriatic coast, whether south in Dubrovnik (per the hopes of the Kosače) or north in Senj (per the hopes of the Frankapani). At the same time, it is also clear that there were other non-political questions that were important to the magnates. Probably the most important was the beauty and youth of the bride; not all the Marzano sisters were considered equally attractive. Also, it is interesting that Ferrante insisted on the magnates paying the dowries themselves, since he believed that the protection and prestige that came with marrying into royalty was enough of an incentive. The fact that Bernardin Frankapan of Modruš and Vlatko Kosača agreed to this shows that they did indeed consider them an investment. In the end the Neapolitan heritage became an important element of their family identity even after the collapse of the Aragonese regime