David Nicolle 
Crusader Castles in Cyprus, Greece and the Aegean 1191 1571 [PDF ebook] 

The castles built by the Crusaders, Hospitallers, Venetians and Genoese in Cyprus, Greece, the Aegean, and on the Black Sea served to defend against a complex array of constantly changing threats: Mamluks, Catalan mercenaries, Ottoman Turks, Byzantines, independent Islamic states, Timur-i-Lenk, and widespread piracy, to name but few. The resulting fortifications some inherited from conquered the territories of the former Byzantine empire, some built from scratch were very different to those found in the Middle East. This superbly illustrated book explores their design, development and fate in detail, documenting the rich architectural heritage of this region and its complex history.