Where I was raised in Northwest Pennsylvania (also known as the Bible Belt or Northern Appalachia) camp meetings were held into the 1930's. Don't know what denomination but they were known as Holy Rollers and we kids being raised as Covenanter Presbyterians (the more dour group) were strictly forbidden to attend. We did however occasionally hide in the bushes to hear the most inspiring shouting and singing. Wish I could have recorded it.