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^ Following the East–West Schism of 1054.^ Tolerated after the Edicts of Serdica (311) and Milan (313) state religion after 380.In 395, the empire was permanently divided in two halves after the death of Theodosius I. ^ Constantinople became the capital of the (united) empire in 330.
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The Empire of Nicaea is considered by historians to be the legitimate continuation of the Byzantine Empire because it managed to retake Constantinople. ^ Between 12 there was an interregnum when the Latin Empire took control of Constantinople, causing the Byzantine Empire itself to be divided into the Empire of Nicaea, the Empire of Trebizond, and the Despotate of Epirus.
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