The religion and its followers faced persecution in the 4th century from Christianization, and Mithraism came to an end at some point between its last decade and the 5th century. Ulansey states that "Mithraism declined with the rise to power of Christianity, until the beginning of the fifth century, when Christianity became strong enough to exterminate by force rival religions such as Mithraism." According to Speidel, Christians fought fiercely with this feared enemy and suppressed it during the late 4thcentury. Mithraic sanctuaries were destroyed and religion was no longer a matter of personal choice. According to Luther H. Martin, Roman Mithraism came to an end with the anti-pagan decrees of the Christian emperor Theodosius during the last decade of the 4thcentury.