The eastern Mediterranean during the period 1291–1352 underwent a series of dramatic transformations which would alter its religious and political makeup for centuries to come. In some senses the period can be considered as one in which the eastern frontiers of Christendom were eroded in the face of unrelenting Islamic expansion. That was certainly the case in the southeastern Mediterranean, where the last of the crusader outposts on the Syrian coast were expunged by the Mamluks of Egypt, who gradually extended their empire across the coast of north Africa and through Syria up to the borders of Asia Minor and Cilician Armenia. This was also the case further north where the Turks quickly overran the Byzantine territories in western Anatolia and began to extend their influence into the Aegean and Greece. By the end of the period the Ottomans were poised to cross into Europe, leading to the Turkish domination of the Balkans and eastern Europe in the later fourteenth and fifteenth centuries.

Crusading at this time changed in response to the expansion of these Muslim groups. Initially plans were made to recover the Holy Land from the Mamluks and as the fourteenth century progressed attention was increasingly turned to halting the advances of the Turks in the Aegean. However, while the expansion of the Mamluks and Turks at the expense of the Byzantines and Latins cannot be disputed, the period should not be simply viewed as one of Islamic expansion and crusade. Italian commercial contacts with the Levant continued despite the loss of the crusader states and the volume of merchant traffic visiting Mamluk ports, as well as the size and importance of Latin merchant colonies, increased throughout the period. In the Aegean especially, things were even more complicated and the policies of the different groups in the region were not always aligned to simplistic religious affiliations: the Turkish principalities were often in conflict with one other, as were the Latin and Byzantine states. In fact most of the Aegean powers fought amongst themselves and made informal alliances and traded with those of different cultural and religious backgrounds when it suited them.

This book examines crusading in the Aegean region during this convoluted and transformative period from the perspective of the Latin merchants who operated there, men like the Genoese Zaccaria lords of Chios or the Venetians who participated in the naval leagues against the Turks.