The book offered to the reader by Arthur Ferguson, written more than forty years ago, sheds completely unexpected light on the usual categories of studying medieval chivalry. In terms of genre, Ferguson’s work is similar to Huizinga’s famous book “Autumn of the Middle Ages” and forms one, paradoxical, but very harmonious whole. Both of them talk about the functioning of the idea of chivalry, revealing the reasons for its existence independent of reality in the dramatically changing conditions of the 15th century. Huizinga's Franco-Burgundian material is offset by completely different and completely specific English material. However, one can hardly speak of continuity between these two studies. Separated by several decades and the stormy waters of the Atlantic Ocean, Huizinga and Ferguson created differently, used different methodologies and addressed different subjects. The book itself consists of six essays on the history of knightly thought rather than knightly practices, interconnected and devoted to various aspects of the manifestation of chivalry in the 15th century: the political, national, educational and intellectual spheres of the functioning of knightly ideas at the end of the Middle Ages.