"Cato's Letters" is a series of essays published in the early 18th century by John Trenchard and Thomas Gordon. These writings advocated for civil liberties, freedom of expression, and the importance of a limited government. They were influential in shaping public opinion and political thought in England and the American colonies. The letters were named after the Roman statesman Cato the Younger, who was known for his commitment to republicanism and opposition to tyranny. Published between 1720 and 1723, "Cato's Letters" played a significant role in the development of liberal political philosophy and inspired later thinkers, including the Founding Fathers of the United States.