Victor Borge knew more about Russian Church music than I ever would have anticipated, judging by this passage:
The rules about sacred music were even stricter. No instruments of any sort were allowed in church, which is why the men in Russian choirs developed those deep, organ-like tones. Women weren't permitted to sing in church at all, which is why the men in Russian choirs developed those high falsetto sounds. Then the Czars tried to figure out why nobody showed up for services. After they got church music messed up enough to suit them, the Czars tried to ban all other types of music, especially if they were fun.