The Decapolis (Greek: deka, ten; polis, city) was a group of ten cities on the eastern frontier of the Roman Empire. The ten cities were not an official league or political unit, but they were grouped together because of their language, culture, location, and political status. The Decapolis cities were centers of Greek and Roman culture in a region that was otherwise Semitic (Jewish, Nabatean, and Aramean). With the exception of Damascus, the "Region of the Decapolis" was located in modern-day northeastern Israel, northwestern Jordan, and southwestern Syria. Each city had a certain degree of autonomy and self-rule.

The names of the traditional Ten Cities of the Decapolis come from the Roman historian Pliny the Elder. They are:

1. Gerasa (Jerash)
2. Scythopolis (Beth-Shean), the only city on the western side of the Jordan River
3. Hippos (Hippus or Sussita)
4. Gadara (Umm Qays)
5. Pella (East of Irbid)
6. Philadelphia, modern day Amman, the capital of Jordan
7. Dion
8. Canatha (Qanawat)
9. Raphana
10. Damascus, the capital of modern Syria; Damascus was considerably north of the others and so is sometimes thought to have been an "honorary" member.

Hellenistic era

The Decapolis was a region where two cultures interacted: the culture of the Greek colonists and the indigenous Semitic culture. There was some conflict. At the same time, there was also some cultural blending and borrowing in the Decapolis region. The cities acted as centers for the diffusion of Greek culture.

The Roman general Pompey conquered Judea in 63 BC. The people of the Decapolis cities welcomed Pompey as a liberator from the Jewish Hasmonean kingdom that had ruled much of the area. In fact, for centuries the cities based their calendar era on this conquest and used 63 BC as their base year. Their calendar is called the Pompeian Era. It is at this time that historians identify the region and the cities with the term "Decapolis."

The Roman Decapolis 

The Roman government wanted Roman culture to flourish in the farthest reaches of the empire, which at the time included eastern Palestine. So they encouraged the growth of these ten cities, allowing them some political autonomy within the protective sphere of Rome. Each city functioned as a polis or city-state, with jurisdiction over an area of the surrounding countryside. Each city also minted its own coins. Many coins from Decapolis cities identify their city as "autonomous," "free," "sovereign," or "sacred," terms that imply some sort of self-governing status.

The Romans strongly left their cultural stamp on all of the cities. Each one was eventually rebuilt with a Roman-style grid of streets based around a central cardo and/or decumanus. The Romans sponsored and built numerous temples and other public buildings.

The cities may also have enjoyed strong commercial ties, fostered by a network of new Roman roads. This has led to their common identification today as a "federation" or "league." The Decapolis was probably never an official political or economic union; most likely it signified the collection of city-states that enjoyed special autonomy during early Roman rule.

Later years 

The term "Decapolis" fell out of use after the emperor Trajan added the province of Arabia to the Roman Empire in the second century AD. The new province was east of Palestine, so the Decapolis was no longer the Greco-Roman cultural front line. In addition, the cities were grouped into different Roman provinces: Syria, Palestina Secunda, and Arabia. However, the Decapolis remained an important cultural region in the Roman east, even though the term was no longer used.

The Roman and Byzantine Decapolis region was influenced and gradually taken over by Christianity. Some cities were more receptive than others to the new religion. In other cities, paganism persisted long into the Byzantine era. Eventually, however, the region became almost entirely Christian, and most of the cities served as seats of bishops.

Most of the cities continued into the late Roman and Byzantine periods. Some were abandoned in the years following Palestine's conquest by the Umayyad Caliphate in 641, but other cities continued to be inhabited long into the Islamic period.

Excavations  

Jerash (Gerasa) and Bet She'an (Scythopolis) survive as towns today, while Damascus and Amman (Philadelphia) have become important capital cities. Twentieth-century archaeology has identified most of the other cities, and most have undergone or are undergoing considerable excavation.

Source: Wikipedia