Westphalia and Free Expression

I found a reference to the Peace of Westphalia in an unlikely place today: in an article on free expression. “The idea of free expression traces itself back to the Peace of Westphalia,” reads the dubious sentence. I understand that the author is trying to connect religious liberty with freedom of thought, and freedom of thought with freedom of expression, but this is a tenuous chain at best. I can assure you that no one in Westphalia was thinking of “freedom of expression” (or speech, or press) when they agreed to the compromises there. Even freedom of religious practice was severely restricted: some religious minorities had their own churches, others were allowed to hold services only in private homes, and many were granted only freedom of conscience.