Jean de Joinville was de Charny's grandfather's. He was a close friend of King Louis IX and author of his biography. In the same tradition, Sir Geoffroi wrote three books in his time. His most famous book was "A Knight's Own Book of Chivalry". In this book he shared his great skill and knowledge of combat. The second book written by de Charny is entitled, "Requests (or Questions) for jousting tournaments and war". It was written about 1352 to the Knights of the Order of the Star which Sir Geoffroi founded. This book was written in the form of questions. His third book was the book "Charny", describes the life of a knight and lists the qualities a good knight must possess.