The “exceptions” are Plato, Aristotle, Cicero, Pufendorf, Grotius, Blackstone, Locke, Sydney, Montesquieu, Hume, Reid, Machiavelli, Milton, Shakespeare, Burke, etc.
The “History” the Founders read (Plutarch, Thucydides, Livy, Polybius) were more like philosophers than the stuffy pencil pushers we call “historians” today.
Note to poly sci types. The Founders read HISTORY not political philosophy. Montesquieu was the exception, not the rule.