It is also happening in India today with Hindus. They persecute and sometimes kill Muslims and Christians. They have laws against conversion. When people of another faith help out locals, they are suspect of doing it with intent to convert.
The Roman church did that to early Protestants when they could. Protestants and Catholics did that to Anabaptists because they left for a different faith.
One of the things they all have in common is that the state and the religion are one. When a religion has the power of the sword, then they take that sword and go after people of other faiths.

