Which event produced a major change in the roman empire's religion? constantine recognized the legality of christianity. muhammad began a campaign of conversion to islam. trade with asia introduced new ideas, such as hinduism. emperor julian renewed the worship of the roman gods.

The answer is A: Constantine recognized the legality of Christianity. This was the biggest change in the Roman Empire to date. Constantine had a change of heart due to a dream he was seen by Jesus- and that is the result he became Christian. In addition, 'the great schism' was a barrier that Constantine and pope were separated (both which they agreed on) due to different ethnicities, languages & culture.

The great schism chart
Constantine's side
East side- middle easterners, Egyptians, turkey
Languages- turkish, Arabica

Pope's side
West side- Rome, Italy
Language- Latin

The Muscovite ruler was recognized as an emperor by Maximilian I, the emperor of the Holy Roman Empire in 1514. However, the first Russian ruler to be formally crowned as "tsar of all Russia" was Ivan IV, until then known as Grand Prince of all Russia (1547)