Names of Istanbul

The city of Istanbul has been known by a number of different names. The most notable names besides the modern Turkish name are Byzantium, Constantinople, and Stamboul. Different names are associated with different phases of its history and with different languages.

According to Pliny the Elder the first name of Byzantium was Lygos. This may have been the name of a Thracian settlement situated on the site of the later city, near the point of the peninsula (Sarayburnu).

Byzantion (Βυζάντιον), Latinized as Byzantium, was founded by Greek colonists from Megara in 667 BC. The name is believed to be of Thracian or Illyrian origin and thus to predate the Greek settlement. It may be derived from a Thracian or Illyrian personal name, Byzas. Ancient Greek legend refers to a legendary king of that name as the leader of the Megarean colonists and eponymous founder of the city.

After its fall, the name "Byzantine Empire" started being used by the West to refer to the Eastern Roman Empire (the Eastern continuation of the Roman Empire during the Middle Ages), whose capital the city had been. This usage was introduced by the German historian Hieronymus Wolf in 1555, a century after the empire had ceased to exist. During the time of the empire, the term Byzantium was used only for the city, not for the empire that it ruled.

The city was called Augusta Antonina for a brief period in the 3rd century AD. The Roman Emperor Septimius Severus (193–211) conferred the name in honor of his son Antoninus, the later Emperor Caracalla.

Before the Roman emperor Constantine the Great made the city the new eastern capital of the Roman Empire on May 11, 330, he undertook a major construction project, essentially rebuilding the city on a monumental scale, partly modeled after Rome. Names of this period included ἡ Νέα, δευτέρα Ῥώμη "the New, second Rome",Alma Roma  Ἄλμα Ῥώμα, Βυζαντιάς Ῥώμη, ἑῴα Ῥώμη "Eastern Rome", Roma Constantinopolitana.

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