Ptolemy, considered a proto-Humanist by some, combined the principles of Northern Italian republicanism with Aristotelian theory in his "De Regimine Principum," a book that influenced much of the political thought of the later Middle Ages, the Renaissance, and the early modern period. He was the first to attack kingship as despotism and to draw parallels between ancient Greek models of mixed constitution and the Roman Republic, biblical rule, the Church, and medieval government.

In addition to his translation of this important and radical medieval political treatise, written around 1300,...

Ancient Greeks and Romans often wrote that the best form of government consists of a mixture of monarchy, aristocracy, and democracy. Political writers in the early modern period applied this idea to government in England, Venice, and Florence, and Americans used it in designing their constitution. In this history of political thought James Blythe investigates what happened to the concept of mixed constitution during the Middle Ages, when the work of the Greek historian Polybius, the source of many of the formal elements of early modern theory, was unknown in Latin. Although it is...