The city allied itself with Rome during the Punic Wars, thereby escaping damage or ruin and entered a relatively peaceful 700-year period under the Pax Romana. Livy tells us that Hadrumetum was the landing place of the Roman army under Scipio Africanus in the second Punic War.
As part of Bonifacius's revolt against Constantinople, the Vandals were invited in and they took Hadrumetum in 434 CE and renamed the town Hunerikopolis. During the Vandalic War Justinian retook the town in 534 CE and restored its Roman name.
Arab conquest  In the 7th century AD Arab-Islamic armies conquered what is now Tunisia and rapidly spread Arab culture across what had been a thoroughly Romanized and Christianized landscape. The Arabs seized the city, which in the aftermath of Rome's fall was but a remnant of its former self. They renamed the city Sûsa and within a few decades elevated it to the status of the main seaport of the Aghlabid Dynasty. When the Aghlabids invaded Sicily in 827, Sûsa was their main staging ground. European pushback [edit] In the centuries that followed, as Europe gained technological ascendancy and began pushing back at Islam, Sûsa was briefly occupied by the Normans in the 12th century, was later more thoroughly occupied by the Spanish, and in the 18th century was the target of bombardments by the Venetians and the French. The French called the city Sousse. Despite the turmoil around it, Sousse's character had retained the solidly Arabian look and feel it had assumed in the centuries after Islam's wars of conquest. Today it is considered one of the best examples of seaward-facing fortifications built by the Arabs. Its ribat, a soaring structure that combined the purposes of a minaret and a watch tower, is in outstanding condition and draws visitors from around the world. Sousse was the site of Chess interzonal in 1967 which was made famous when American Grandmaster Bobby Fischer withdrew from the tournament even though he was in first place at the time.  These days, Sousse, with a population of about 200,000, retains a medieval heart of narrow, twisted streets, a kasbah and medina, its ribat fortress and long wall on the Mediterranean. Surrounding it is a modern city of long, straight roads and more widely spaced buildings. It is only 20 km from the international airport of Monastir. The fine sandy beaches are backed by orchards and olive groves. It has a Mediterranean climate, with hot, dry summers and warm, mild wet winters. The seaside location moderates the climate, making it an all-season resort. Some 1,200,000 visitors come every year to enjoy its hotels and restaurants, nightclubs, casinos, beaches and sports facilities. A Medina, surrounded by its city walls and fortifications, is of historical interest. The Medina includes open and covered bazaars (souks). Buildings of historical interest include the ribat castle, the central mosque, and a historical museum in the Casbah with mosaics from the area's many Roman villas. The Carthaginian catacombs can be visited. UNESCO declared the medina of Sousse a World Heritage Site in 1988, citing among other things its preservation from modern development.