Cato’s Letters were letters published in 18th cent. Britain, focused on the concept of liberty and questioned tyrannical authority structures.
The Declaration of Independence famously spoke of right to “the pursuit of happiness,” a phrase that has been questioned as to its extent and meaning.
Algernon Sidney was a fervent republican whose philosophy and politics, as well as his eventual martyrdom, influenced democratic revolutionaries who followed him.
British Whigs were early supporters of constitutionalism and later continued to work for a platform of classical liberalism and republicanism.
Stoicism was a philosophical movement in Ancient Greece and Rome based on rational self-discipline, virtue, and natural law as the basis for state authority.