The role of Byzantine influence cannot be ignored in any account of the cultural and historical background of ninth century literature. One should recall that the Carolingian period was an era of general European intercourse which could not fail to have an effect upon society. The foreign relations of the Frankish Empire necessitated much traveling, visiting and correspondence. Warlike as well as peaceful movement, commercial or cultural, increased the interchange of ideas. There was an overlapping of boundary lines, too, which amalgated populations. The infiltration of Byzantine influence might be conceived as a by-product of European intercourse. Insofar as hymnology is concerned, musical contacts between the Byzantine and Frankish realms were frequent. As early as Pippin’s reign, Byzantine musicians appeared at the Frankish court with a gift of an organ from the Emperor Constantinus Copronymus.[15] Many refugee monks who fled to the west during the iconoclastic controversy remained there even after its close in 787, enjoying monastic hospitality and imperial favor. Charlemagne permitted them to use the Greek language in worship and was so much impressed by the music employed in chanting the psalms that he caused it to be adopted for the Latin version also.[16] The paramount influence of Byzantine music upon liturgical practice in the west will be considered more fully in connection with the sequence. Verifiable traces of Byzantine influence had already appeared with the activities of Gregory the Great and are entirely comprehensible, so far as he is concerned, in view of his residence at Constantinople, 579-585, as papal envoy of Pelagius II.[17] The importation of litanies into the west illustrates this type of influence. When Charlemagne received the Sacramentary from Pope Hadrian I, it was labelled “Gregorian.” But in the interval between the lives of Gregory and Charlemagne, popes of eastern origin, ruling at the end of the seventh and the beginning of the eighth century were responsible for western practice.[18] The influence of the Eastern upon the Western Church seems to have been cumulative, with Charlemagne in his day acting as the agent for its diffusion throughout the Frankish Church. In matters concerning the church and its worship the Greeks were an acquisition not only as musicians but as scholars and as experts in the fine arts. Their scholarship was in demand in New Testament studies. Illustrations of Greek and of oriental inspiration in general are numerous in architecture, painting, sculpture, ivories, work in precious metals and the decoration of manuscripts.[19] Perhaps it was a natural desire to emulate the splendor and ornament of eastern rites which led Charlemagne to favor Greek elements in western observance at the expense of the Gallican.