In this paper the author shall focus on the circulation of the narrative materials which were commonly used in the big compilations on Charlemagne's reign in Medieval Europe. Not only does the network of Latin sources spread more or less simultaneously in different parts of Europe in the 13th century, it also created a pattern and a common tendency to develop narrative insertions. Thus, it was of great influence on the circulation of vernacular epics. To sustain this observation, the author shall illustrate with examples taken in three of these Charlemagne-cycles: the French Chronique Rimée, the Welsh Ystoria de Karolo Magno and the Norse Karlamagnússaga.