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Classical period

Alexander the Great 's conquest of the Persian Empire in 332 BC introduced Hellenistic culture to the Middle East. After Alexander's death in 323 BC, the empire split among his generals, and in the end much of Transjordan was disputed between the Ptolemies based in Egypt and the Seleucids based in Syria. The Nabataeans, nomadic Arabs based south of Edom, managed to establish an independent kingdom in 169 BC by exploiting the struggle between the two Greek powers. The Nabataean Kingdom controlled much of the trade routes of the region, and it stretched south along the Red Sea coast into the Hejaz desert, up to as far north as Damascus, which it controlled for a short period (85–71) BC. The Nabataeans massed a fortune from their control of the trade routes, often drawing the envy of their neighbours. Petra, Nabataea's barren capital, flourished in the 1st century AD, driven by its extensive water irrigation systems and agriculture. The Nabataeans were also talented stone carvers, building their most elaborate structure, Al-Khazneh, in the first century AD. It is believed to be the mausoleum of the Arab Nabataean King Aretas IV.

Roman legions under Pompey conquered much of the Levant in 63 BC, inaugurating a period of Roman rule that lasted four centuries. In 106 AD, Emperor Trajan annexed Nabataea unopposed, and rebuilt the King's Highway which became known as the Via Traiana Nova road. The Romans gave the Greek cities of Transjordan—Philadelphia (Amman), Gerasa (Jerash), Gedara (Umm Quays), Pella (Tabaqat Fahl) and Arbila (Irbid)—and other Hellenistic cities in Palestine and southern Syria, a level of autonomy by forming the Decapolis, a ten-city league. Jerash is one of the best preserved Roman cities in the East; it was even visited by Emperor Hadrian during his journey to Palestine.

In 324 AD, the Roman Empire split and the Eastern Roman Empire, later known as the Byzantine Empire, continued to control or influence the region until 636. Christianity had become legal within the empire in 313 after co-emperors Constantine and Licinius signed an edict of toleration. In 380, the Edict of Thessalonica made Christianity the official state religion. Transjordan prospered during the Byzantine era, and Christian churches were built everywhere. The Aqaba Church in Ayla was built during this era, it is considered to be the world's first purpose built Christian church. Umm ar-Rasas in southern Amman contains at least 16 Byzantine churches. Meanwhile, Petra's importance declined as sea trade routes emerged, and after a 363 earthquake destroyed many structures, it declined further, eventually being abandoned. The Sassanian Empire in the east became the Byzantines' rivals, and frequent confrontations sometimes led to the Sassanids controlling some parts of the region, including Transjordan.