This book collects previously published articles and papers concerning the specificities of medieval Ottoman history, in particular the interactions and streams of influence relating the late Byzantine Empire, the early Ottoman Empire and humanist Europe. Author Michel Balivet is a specialist in Turkish and Byzantine history and professor at the University of Provence. In the first section of this volume, he presents the role of Turkic speaking people in the crusades as a key to understanding not only the history of the crusades but also of the Muslim world in the 11th to the 13th century. The second section of the book demonstrates and explains the dynamic character of Turkish science in the 14th and 15th century particularly in the fields of medicine, pharmacopoeia, and medical institutions. In the third section, Balivet discusses the Byzantine and Ottoman cultural exchange and political rapprochement in the last centuries of the Middle-Ages. This rich volume would be of interest to people interested in the medieval history of the Turks, Seljuks, Turkmen and Ottomans.