Diocletian and the Great Persecution

Diocletian
The Roman Emperor Diocletian came to power in 284 AD. He was an army general, and he felt that a lot of the empire's problems could be solved by not allowing so much freedom, but instead having everyone do the same thing, the right way (his way). First he was busy fighting the Germans and the Sassanids and having civil wars, then for a while he was busy trying to fix the economy.
Diocletian's palace at Split (the bell tower was added later)
But by 301
AD Diocletian had noticed that there were
people who had different religions
in the Roman Empire. Diocletian HATED this idea. First of all, these
people were different from him, which seemed disrespectful. Second,
they might be making the gods
mad. So they had to be stopped. First Diocletian got rid of the Manichaeans.
Then (since that had gone pretty well), in 303 AD
he began a big persecution of the Christians.
This didn't go as well. Diocletian's co-emperors in the West weren't
very interested in killing Christians, so a lot of Eastern Christians
just moved to the West. Also, even Diocletian didn't really want to
kill a whole lot of people. He just wanted them to worship his gods.
He didn't really know what to do with the ones who said no.
Galerius
Even after Diocletian retired in 305 AD, his successor, Galerius, still
persecuted the Christians, but still without getting rid of them.