The in game tool tip says the Remove Heresy will remove "other" religions from the city... but how does the game decide what is the "other" religion?
Here is what happened to me...
I founded Christianity in my capital which became the Holy City. The Dutch sent a Great Prophet to my capital (which apparently can enter your civ even without open borders) and converted my capital to Buddism.
Ok, so I figured I would buy an inquisitor to remove this other religion because I'm thinking "other" would mean, not the one I founded. Well, I used the inquisitor and it removed the 2 people left who were still following Christianity making the city 100% Buddidism. So basically my inquisitor actually helped my enemy and hurt me.
Ok, so now I was thinking the inquisitor must consider the "other" religion to be the one that is not majority. So I loaded up an autosave to test this out. This time I sent the Inquisitor to another one of my cities where Christianity was the majority religion with only 1 follower of Buddism. Well, guess what? The inquisitor removed all the followers of Christianity and converted the city to Buddism!
So does this mean that whatever religion my capital is following at the moment becomes my "state religion" and my inquisitors will remove anything else, including the religion that I founded?
If so, how do I get the followers of Buddism out of my Holy City and convert it back to the religon I founded? I guess I have to use a missionary to re-spread my religon and convert people back to Christianity but now I really don't understand how to use an inquisitor. It seems to always remove the followers that I dont want to remove.