[1][2] Byzantium was colonized by Greeks from Megara in the 7th century BC and remained primarily Greek-speaking until its conquest by the Ottoman Empire in AD 1453.

[7] The name Lygos for the city, which likely corresponds to an earlier Thracian settlement,[4] is mentioned by Pliny the Elder in his Natural History.

[8] Byzántios, plural Byzántioi (Ancient Greek: Βυζάντιος, Βυζάντιοι, Latin: Byzantius; adjective the same) referred to Byzantion's inhabitants, also used as an ethnonym for the people of the city and as a family name.

Tradition says that Byzas of Megara (a city-state near Athens) founded the city when he sailed northeast across the Aegean Sea.

[14] After siding with Pescennius Niger against the victorious Septimius Severus, the city was besieged by Roman forces and suffered extensive damage in AD 196.

[17] The strategic and highly defensible (due to being surrounded by water on almost all sides) location of Byzantium attracted Roman Emperor Constantine I who, in AD 330, refounded it as an imperial residence inspired by Rome itself, known as Nova Roma.

It was a commercial, cultural, and diplomatic centre and for centuries formed the capital of the Byzantine Empire, which decorated the city with numerous monuments, some still standing today.

By the late Hellenistic or early Roman period (1st century BC), the star and crescent motif was associated to some degree with Byzantium; even though it became more widely used as the royal emblem of Mithradates VI Eupator (who for a time incorporated the city into his empire).

[18] Some Byzantine coins of the 1st century BC and later show the head of Artemis with bow and quiver, and feature a crescent with what appears to be an eight-rayed star on the reverse.

On a particularly dark and wet night Philip attempted a surprise attack but was thwarted by the appearance of a bright light in the sky.

[22][23][24] It is unclear precisely how the symbol Hecate/Artemis, one of many goddesses[c] would have been transferred to the city itself, but it seems likely to have been an effect of being credited with the intervention against Philip and the subsequent honors.

This was a common process in ancient Greece, as in Athens where the city was named after Athena in honor of such an intervention in time of war.

"[26] The wide variety of these issues, and the varying explanations for the significance of the star and crescent on Roman coinage precludes their discussion here.