The Spirit of the Laws
He is the principal source of the theory of separation of powers, which is implemented in many constitutions throughout the world. He is also known for doing more than any other author to secure the place of the word "despotism" in the political lexicon. His anonymously published "The Spirit of the Laws" (1748), which was received well in both Great Britain and the American colonies, influenced the Founding Fathers of the United States in drafting the U.S. Constitution.