The book "Lorenzo Valla's Treatise on the Donation of Constantine" is an important work of the Italian humanist Lorenzo Valla, in which he examines the legendary "Donation of Constantine" - a document that established the rights of the Pope on the territory of the Western Roman Empire. The author carefully analyzes the text of the document, revealing its contradictions and falsity. This work of Valla played a significant role in questioning the historicity of the Donation of Constantine and influenced the further development of views on the authority of the Pope and his relationship with the secular authorities. After reading this book, the reader will have the opportunity to better understand the complex aspects of the relationship between religion and politics in medieval Europe.