 The letter, believed dated several months before the Philadelphia convention, refers to an offer the prince had received substantially similar to that detailed in the original story.In it, Henry reports he is not interested in an American crown but recommends, instead, that an unnamed French candidate be considered for the position.Some have attributed the natural-born-citizen clause in the U.S. constitution as an attempt by the Philadelphia Convention to end the persistence of rumors of European royalty being invited to assume a hypothetical United States throne.