Constantin François de Chassebœuf, comte de Volney (3 February 1757 – 25 April 1820) was a French philosopher, abolitionist, historian, orientalist, and politician. He was at first surnamed Boisgirais after his father's estate, but afterwards assumed the name of Volney (which he had created as a contraction of Voltaire and Ferney).

Sometime during his stay in the United States, he and Thomas Jefferson entered into a secret arrangement whereby Jefferson agreed to translate Volney's Ruins of Empires into English. Volney visited Monticello for two weeks during June 1796. The two men also met on several occasions at the American Philosophical Society (APS). Jefferson was President of APS at the time and sponsored Volney's induction into the organization. These meetings provided the two men with ample opportunity to conceive and discuss the translation project.

Jefferson, then serving as Vice President under John Adams, appreciated the book's central theme – that empires rise if government allows enlightened self-interest to flourish. This theme, Jefferson believed, represented an excellent summary of the Enlightenment-based principles upon which the U.S. was founded. However, Jefferson insisted that his translation be published only for certain readers, due to the book's controversial religious content. Jefferson was preparing to make a bid for the Presidency of the United States in 1800; he was worried his Federalist opponents would attack him as an atheist, if it were known he translated Volney's supposedly heretical book.

According to the evidence discovered by the French researcher Gilbert Chinard (1881-1972), Jefferson translated the invocation plus the first 20 chapters of the 1802 Paris edition of Volney's Ruins. These first 20 chapters represent a review of human history from the point of view of a post-Enlightenment philosopher. Presumably, Jefferson then became too occupied with the 1800 Presidential campaign and didn't have time to finish the last four chapters of the book. In these chapters Volney describes "General Assembly of Nations," a fictionalized world convention wherein each religion defends its version of "the truth" according to its particular holy book. Since no religion is able to scientifically "prove" its most basic assertions, Volney concludes the book with a call for an absolute separation of church and state:

From this we conclude, that, to live in harmony and peace…we must trace a line of distinction between those (assertions) that are capable of verification, and those that are not; (we must) separate by an inviolable barrier the world of fantastical beings from the world of realities…

Since Jefferson did not have time to complete the translation project, the last four chapters were translated by Joel Barlow, an American land speculator and poet living in Paris. Barlow's name then became associated with the entire translation, further obscuring Jefferson's role in the project.