I can remember a time in my own lifetime when freedom of religion was frequently interpreted to mean you could be whatever flavor of Christian you wanted to be. In time, the language of religious freedom generally started to include non-Christian religions. It was still more time before the notion of religious freedom began to include the notion of freedom from religion altogether. Atheism used to be a much more fringe viewpoint, so much so that many people didn’t even fully understand what it meant. Atheists with the courage to speak up back when it was still a largely fringe viewpoint played a significant role in promoting freedom of religion. This applies even to those who, while not atheists themselves, held minority and perhaps unpopular religious views.