I watched the TV show The Tudors. What stirred everything up over there was the King changing the Kingdom's official religion. He wanted a divorce and the Catholics would not let him, so he changed the official religion of England.

The founding father's were all God fearing people. They just didn't want the United States to have an official church. And contrary to myths, there was not any atheists among them. Maybe a few Agnostics, that's all.