It's hard to trace the official adoption of Christianity by the Roman Empire to one event, but a good candidate is the Battle of the Milvian Bridge on October 28 - in the year 312. On that day, Constantine the Great consolidated control over the empire by defeating the rival Emperor Maxentius. On the eve of battle, Constantine had received a vision in which he was promised victory if he used the cross as his battle standard.
1000 years later, beliefs sprang up that one millennium of Christian rule meant Christ would soon be returning to Earth.
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A Korean Christian group named Mission for the Coming Days believed that Hyoo-Go - the Rapture - would occur in 1992. They placed billboard ads and a spread in USA Today on October 28 of that year announcing the end of the world.
