"..Constantine’s reign (312–337) saw significant and lasting changes to the Roman Empire. Christians, who had been tolerated at best—but often tortured or killed—found new favour after the Edict of Milan (313) assured toleration for all religions. From about 320 the Roman state no longer persecuted Christians but rather showered Christian institutions with patronage. In 324 Constantine relocated the imperial capital to Byzantium (which was renamed Constantinople), a move whose strategic and economic benefits helped reinvigorate the state for some time. But Constantine failed to save the empire from decline. The last of his line, Theodosius I (379–395), was the last emperor to rule over a unified Roman Empire. The Western Empire, suffering from repeated invasions and the flight of the peasants into the cities, had grown weak compared with the East, where spices and other exports virtually guaranteed wealth and stability. When Theodosius died, in 395, Rome split into Eastern and Western empires.
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