The Turkish name of the city is Trabzon. It is historically known in English as Trebizond. The first recorded name of the city is Τραπεζοῦς (Trapezous), referencing the table-like central hill between the Zağnos (İskeleboz) and Kuzgun streams on which it was founded (τράπεζα meant "table" in Ancient Greek; note the table on the coin in the figure.) In Latin, Trabzon was called Trapezus, which is a latinization of its ancient Greek name. Both in Pontic Greek and Modern Greek, it is called Τραπεζούντα (Trapezounta). In Ottoman Turkish and Persian, it is written as طربزون. During Ottoman times, Tara Bozan was also used. Some western geographers used this name instead of the Latin Trebizond. In Laz it is known as ტამტრა (T'amt'ra) or T'rap'uzani, in Georgian it is ტრაპიზონი (T'rap'izoni) and in Armenian it is Տրապիզոն Trapizon. The 19th-century Armenian travelling priest Byjiskian called the city by other, native names, including Hurşidabat and Ozinis. Other versions of the name, which have incidentally been used in English literature as well, include: Trebizonde (Fr.), Trapezunt (German), Trebisonda (Sp.), Trapesunta (It.),Trapisonda, Tribisonde, Terabesoun, Trabesun, Trabuzan, Trabizond and Tarabossan.
Before the city was founded as a Greek colony the area was dominated by Colchian (Caucasian) and Chaldian (Anatolian) tribes. It is possible that the settlement origins of Trabzon go back to these tribes. The Hayasa, who had been in conflict with the Central-Anatolian Hittites in the 14th century BCE, are believed to have lived in the area south of Trabzon. Later Greek authors mentioned the Macrones and the Chalybes as native peoples. One of the dominant Caucasian groups to the east were the Laz, who were part of the monarchy of the Colchis, together with other related Georgian peoples.
According to Greek sources the city was founded in classical antiquity in 756 BCE as Τραπεζοῦς (Trapezous), by Milesian traders from Sinope. It was one of a number (about ten) of Milesian emporia or trading colonies along the shores of the Black Sea. Others included Abydos and Cyzicus in the Dardanelles, and nearby Kerasous. Like most Greek colonies, the city was a small enclave of Greek life, and not an empire unto its own, in the later European sense of the word. As a colony Trapezous initially paid tribute to Sinope, but early banking (money-changing) activity is suggested occurring in the city already in the 4th century BCE, according to a silver drachma coin from Trapezus in the British Museum, London. Cyrus the Great added the city to the Achaemenid Empire, and was possibly the first ruler to consolidate the eastern Black Sea region into a single political entity (a satrapy).
Trebizond's trade partners included the Mossynoeci. When Xenophon and the Ten Thousand mercenaries were fighting their way out of Persia, the first Greek city they reached was Trebizond (Xenophon, Anabasis, 5.5.10). The city and the local Mossynoeci had become estranged from the Mossynoecian capital, to the point of civil war. Xenophon's force resolved this in the rebels' favor, and so in Trebizond's interest.
Up until the conquests of Alexander the Great the city remained under the dominion of the Achaemenids. While the Pontus was not directly affected by the war, its cities gained independence as a result of it. Local ruling families continued to claim partial Persian heritage, and Persian culture had some lasting influence on the city; the holy springs of mt. Minthrion to the east of the old town were devoted to the Persian-Anatolian Greek god Mithra. In the 2nd century BCE the city with its natural harbours was added to the Kingdom of Pontus by Pharnaces I. Mithridates VI Eupator made it the home port of the Pontic fleet, in his quest to remove the Romans from Anatolia.
After the defeat of Mithridates in 66 BCE the city was first handed to the Galatians, but it was soon returned to the grandson of Mithradates, and subsequently became part of the new client Kingdom of Pontus. When the kingdom was finally annexed to the Roman province of Galatia two centuries later, the fleet passed to new commanders, becoming the Classis Pontica. The city received the status of civitas libera, extending it judicial autonomy and the right to mint its own coin. Trabzon gained importance for its access to roads leading over the Zigana Pass to the Armenian frontier or the upper Euphrates valley. New roads were constructed from Persia and Mesopotamia under the rule of Vespasian. In the next century, the emperor Hadrian commissioned improvements to give the city a more structured harbor. The emperor visited the city in the year 129 as part of his inspection of the eastern border (limes). A mithraeum now serves as a crypt for the church and monastery of Panagia Theoskepastos (Kızlar Manastırı) in nearby Kizlara, east of the citadel and south of the modern harbor.
Trebizond was greatly affected by two events over the following centuries: in the civil war between Septimius Severus and Pescennius Niger, the city suffered for its support of the latter, and in 257 the city was pillaged by the Goths, despite reportedly being defended by "10,000 above its usual garrison", and being defended by two bands of walls.