Fictional and constructed religions

What can fictional religions tell us about real religions? Are constructed religions just as valid as ancient ones? What about real-world religions based on fictional ones? One impetus for creating constructed religions is for use in jurisdictions where religious activity is imposed by the authorities – but people often find that their joke religion then takes on a life of its own.

Fictional religions

Three of my favourite fictional religions were invented by Ursula le Guin: The Telling, the...