The Book of the Body of Policy was the first political treatise written by a woman c. 1407. It counsels the knights, noblemen, and common people on what they must do to end the great political and social unrest occurring during the Hundred Years War (1337-1453) between France and England. In Part I, she addresses how people of all classes must work together to have a just land. She teaches:
“The knights and noblemen hold the place of the hands and arms. As the arms of a man are strong to sustain labor and pain, they must defend the rights of the prince and the commonwealth; and they are also the hands because, as the hands discard harmful things, they must get rid of all that is destructive or unprofitable. The common people are like the stomach, feet and legs. As the stomach receives all that sustains the head and the limbs, the deeds of the prince and nobles must turn to the good and the love of the commonwealth, as will be declared hereafter. As the legs and feet support the actions of the human body, similarly the laborers support all the other estates.”
Part II addresses how the nobility must cultivate virtue and honor. Part III speaks of how to bring up the children of princes. Part IV speaks of the type of person who should guide the children of princes. In Part V, the author discusses what lessons a prince's children should receive. Part VII addresses the proper advice to give a young prince. Part VIII covers the proper observances toward God and the law a prince should hold. Finally, in Part IX, Christine speaks of how a good prince must be like a good shepherd. In this part, she compares the attributes a good knight should have to those qualities found in an excellent guard dog, such as loyalty and protection. (Translated by Diane Bornstein from the Middle English, Cambridge U. Lib. Ms. Kk. 1.5)
In 1410, she wrote The Book of Deeds of Arms and of Chivalry. The book is a synthesis of military treatises from late antiquity, through more contemporary military strategy. She had access to the libraries of the French and Burgundian courts and translations of ancient works, including the Italian scholars of her time. She was not a mere translator of previously written works into the current French vernacular. de Pizan analyzed the older and contemporary ideas on military law and training and organized them into a comprehensive tutorial for young French nobles on the conduct of warfare. The book was in the libraries of the leading French leaders under Charles VII. It was among the first works to be published—in French in 1488 and English in 1489.
Military historians ignored the book because they believed it to be the mere regurgitation of the earlier military manuals and treatises on chivalry because they never translated the late medieval vernacular text into their own language. For instance, they missed her extremely accurate description of how to properly employ gunpowder artillery during the midpoint of the Hundred Years' War. Nor did they note the first-hand information she collected on military strategy from “wise knights” of her time.