The source are unanimous in speaking of Sinope as Diogenes’ birthplace. In  the late fifth century B.C, Sinope was a flourishing Greek town located at the midpoint of the southern coast of the Euxine (the Black Sea) in a region known as Paphlygonia. Legends speak of the Amazons as having founded Sinope and as having named in honor of Sinova, their queen. Another tradition ascribes its foundation to Autolycus, the companion of Hercules. There are indications that a Milesian colony had been established in Sinope  already by the year 756 B.C., and it is unquestionable that by the middle of the seventh century B.C. the presence of the Milesians and other Ionian settlers had shaped the character and the culture of the town. In 444 B.C., the Athenians under Pericles overthrew a local tyrant and established a democratic form of government that would remain in existence until the Persians, led by a satrap named Datames, captured the town around the year 375 B.C. the Persians remained in control of the town until the presence of Alexander’ s power was felt throughout Asia Minor, when it regained its independence and asserted its ancient Hellenic heritage. It is reasonable to assume that, like many others Sinopeans, Diogenes came from the same Milesian stock from which philosophers like Thales, Anaximander and Anaximenes came, and that his language and heritage were purely Greek.
During Diogenes early years, Sinope enjoyed its most prosperous epoch and was the most imported Greek settlement on the shores of the Euxine. Many years after Diogenes, Strabo would have leave for us a description of a happy and affluent Greek town, adorned with temples and fortifications, proud of its gymnasium and market place, and filled with fine buildings and comfortable homes .
The modern town of Sinop, the capital of a northern province in modern Turkey, is a remote descendant of the Greek town where Diogenes was born. With a population of less than 25.000 inhabitants, Sinope still displays today the vestiges of the Hellenic presence of its ancient past.