According to a traditional view one of the main concerns of the early modern Venetian authorities was the question how to avoid a conflict with the Ottoman Empire, quite often described in terms of a front of a natural clash between Christendom and the Islamic word. Altough this vision was put in doubt by the recent historiography, it seems clear that the diplomatic enoys of the Most Serene Republic to the Sublime Porte did not perceive the receiving state of their missions as part of a diplomatic commonwealth of ‘‘Christian princes”, a natural environment of their work. The most obvious reason for this exclusion was the religion, but other excluding factors as frequently described Ottoman tyranny and opression were also recalled in this context. While the Venetian perception of the Ottoman Empire as excluded from the Christendom is quite clear, the diplomats of the Most Serene Republic needed to face a bigger conceptual problem. It was related to a proper definition of possible Venetian allies in the anti-Ottoman struggle (as Persia or Eastern Christians) that apparently did not belong to a traditionally understood Christendom. The aim of the paper is to analyse the criteria of identification of these allies located outside the traditional Christendom. By analyzing the reports and dispatches sent by the Venetian diplomats and consuls to the headquartes in the late 16th and first half of the 17th century I will try to reply to the following questions: To what extent could a different religion or confession serve as including/excluding factor in case of these hybrid territories? Which other factors were used to this scope? Were these factors used only as a political justification of need of an alliance? Finally, I am going to reflect if it is possible to find a perception of ‘‘Christendom’s/Western values” in the diplomatic descriptions of Persian, Ottoman or Eastern Christians’ reality.