During the final centuries of Byzantine rule, the city of Constantinople, unable to recover completely from the effects of the Fourth Crusade (1204) and continuously challenged from two directions by the western world and the Ottomans, could no longer live up to its former glory and reputation as the magnificent capital of a powerful empire. Yet, surprisingly, the critical circumstances of the late Byzantine period that negatively affected almost every aspect of life in the city did not affect its commercial function to the same extent. Hence, despite persistent political, social, economic, and demographic problems during the last fifty years preceding the Ottoman conquest, Constantinople still continued to function as a lively commercial center where Byzantine merchants operated side by side with foreigners, including Italians, Catalans, Ragusans, Ottomans, and others. But the most active group of foreign merchants operating in Constantinople were the Italians, particularly the Venetians and the Genoese, who had established more or less autonomous trade colonies in the city and enjoyed commercial privileges (most importantly exemptions from customs duties) since the eleventh-twelfth centuries. Amplified and made more extensive during the Palaiologan period (1261-1453), these privileges pushed the native merchants of the Byzantine capital into a clearly disadvantaged position vis-à-vis their foreign competitors.