To build on sibling's points about how Constantine was simply throwing official weight behind a true grass-roots movement, you can look at what happened to Elag

To build on sibling's points about how Constantine was simply throwing official weight behind a true grass-roots movement, you can look at what happened to Elagabalus for an example of top down religious change that blew up: https://en.wikipedia.org/wiki/Elagabalus#Religious_controversy https://en.wikipedia.org/wiki/Elagabalus#Religious_controver...