The Czechs and the Hungarians is the answer.
I hope this helps ya :)
The Roman empire was well organized with good roads & active trade, so the new religion could spread easily. Constantine was a sun worshipper who feigned Christianity so he could take control and throw out it's one and only goal
The first step in solving labor problems and carry out the change is the negotiation of the workers, for a better benefit; better wages,health benefits paid sick/holidays as well a chance to grow with the company.