Following the Thirty Years' War, a European religious conflict that embroiled much of the continent, the Peace of Westphalia in 1648 established the notion of territorial sovereignty as a norm of noninterference in the affairs of other states, so-called Westphalian sovereignty, even though the actual treaty itself reaffirmed the multiple levels of sovereignty of the Holy Roman Empire. This resulted as a natural extension of the older principle of "cuius regio, eius religio" (Whose realm, his religion), leaving the Roman Catholic Church with little ability to interfere with the internal affairs of many European states. It is a myth, however, that the Treaties of Westphalia created a new European order of equal sovereign states.