As a Megaran colony, Byzantion was the type of Greek colony that was known as an apoikia. Although the eponymous magistrate (the highest government official by whose name the years in which he served were commemorated) in the other Megaran colonies was the basileus, in Byzantion this official was known as the hieromnamon. Byzantion also had a council called the pentekaideka (fifteens). It is known that Byzantine society was divided into classes of a hundred people, known as hekatostys; Bathonea, Philoktorea and Krateinea are examples of specific hekatostys classes.
In addition to people who were considered to be natural citizens, there were also some foreigners with a privileged status in Byzantium who were called metoikoi. These residents are mentioned in the text attributed to Aristotle entitled Oikonomika. The foreigners with privileges could not own land. As we learn from the same source, in times of economic crisis the Byzantines would rent fertile public land for a limited time and vacant land for an indefinite period of time. Other public domains such as gymnasion, agora and harbors were given to clergyman in exchange for property that had been confiscated from them.
From Aristotle we learn about occupational types in Byzantium, such as fishermen, salt merchants, jugglers, psychics and sorcerers. These workers would pay one third of their income in taxes. Byzantine tombstones that record the occupation of the deceased have also been found. We have examples of astronomers, a midwife, a female doctor, called a mousa, a paidagogos (teacher) whose name was Athenodoros, a judge named Apollonnides (from Miletus), and another judge whose name was Iatrokles (from Milas). Today, the tombstone of the teacher is kept in the Museum of Natural History at the Smithsonian Institute in Washington, D.C. This tombstone was found during an excavation in the Taksim area of Istanbul in 1912. On the tombstone, which dates from the second century B.C., a short, bearded, male figure is sitting on a diphros (stool), directly above which is written “Paidagogos Athenodoros, farewell.” The word paidagogos on the tombstone actually refers to a kind of household slave who took the children to school and helped them with their homework and education.
Another piece of information gleaned from Aristotle is that, in addition to renting their land in times of economic crisis, the Byzantines would call back the merchant ships that were travelling in the Black Sea. It is clear that fishing and agriculture were important sources of income, and customs fees collected from the vessels that passed through the Bosphorus helped to strengthen the Byzantine economy. Sources mention commerce between Byzantion and countries located on the northern shores of the Black Sea. The economic development of a city like Byzantium that is positioned next to an important strait like the Bosphorus is in direct proportion to the commercial traffic that passes through the strait.
As can be understood from coins, starting from the end of the fifth century B.C. Byzantion was on friendly terms with Khalkedon (known today as Kadıköy). The coins of the two cities are similar, both having a type of cattle depicted on them. On Byzantine coins there is a cow over a dolphin, while on Khalkedon coins we find a bull placed over a stalk of wheat. Furthermore, in the second century B.C., this relationship developed to such a level that the names of both cities were engraved on the same coins.
We know that the Byzantines supported Cyzicus during attacks led by Arrhidaios, one of Alexander’s generals and the satrap of the Phrygian Hellespont, on Cyzicus in 319 B.C., which is further evidence that Cyzicus (the modern city of Erdek) in Mysia was on good terms with Byzantion. Also, both cities shared the land by the Lake Daskylitis (Lake Manyas today) and probably the fish in the lake as well. The Byzantines were also an ally of Perinthos (today Ereğli, on the Marmara).
Byzantion’s good rapport with its neighbors continued during the era of the Roman Empire, when homonoia (ally) coins were shared between Nicaea (İznik) and Bizye (Vize in Trakya). Homonoia coins were issued by Nicaea during the reigns of Trebonianus Gallus, Volusianus, Valerian I., Gallienus and Macrinus, and with Bizye in the reign of Philip I. (the Bizye coins were minted in Bizye). Some of the coins have been engraved with the figure of a bonito fish.
Byzantion started to issue coins 250 years after being established. There are a few reasons for this delay in production. First, in Byzantion’s commerce with the Pontos (Black Sea) during the seventh and the sixth centuries B.C. a barter system was dominant, rather than a currency exchange system; secondly, later in the sixth and the fifth centuries B.C. the gold stater of Cyzicus was the only currency accepted in this region. Much like the American dollar, it was a standard currency. In ancient sources by authors such as Aristophanes, it is mentioned that Byzantium issued iron coins at the end of the fifth century B.C., but we do not have any surviving examples of such coins today. The earliest known silver Byzantine coins are dated at the end of the fifth century B.C. or the beginning of the fourth century B.C. The city continued to issue coins, albeit with interruptions, until the rule of Roman emperor Gallienus. Until the start of the Roman imperial period, the heads of gods and goddesses were depicted on the obverses of the coins, but beginning with the Roman Empire, emperors’ heads were engraved on coins. In addition, the crescent and star pattern, similar to that found on the modern Turkish flag, was used 2,000 years ago on Byzantine coins during the Roman period.