Individual #Roman_Empire  an empire including the lands in Europe and Africa and Asia that were ruled by ancient Rome
  instance of:  empire
  member:  Roman.European
  part of:  Africa  Asia  Europe
  part:  Holy_Roman_Empire__First_Reich  the lands ruled by Charlemagne; a continuation of the Roman Empire in Europe
  part:  Byzantine_Empire__Eastern_Roman_Empire  a continuation of the Roman Empire in the East after AD 330 when Constantine the Great rebuilt Byzantium and called it Constantinople and made it his capital
     part:  Byzantium  an ancient city on the Bosporus founded by the Greeks; site of modern Istanbul

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