A large fortified city under the influence of the Parthian Empire and capital of the first Arab Kingdom, Hatra withstood invasions by the Romans in A.D. 116 and 198 thanks to its high, thick walls reinforced by towers. The remains of the city, especially the temples where Hellenistic and Roman architecture blend with Eastern decorative features, attest to the greatness of its civilization.
Hatra is an excellent example of the fortified cities laid out on the circular plan of the eastern city, such as Ctesiphon, Firouzabad or Zingirli. The perfect condition of the double wall in an untouched environment sets it aside as an outstanding example of a series which covers the Parthian, Sassanid, and early Islamic civilization. It provides, moreover, exceptional testimony to an entire facet of Assyro-Babylonian civilization subjected to the influence of Greeks, Parthians, Romans and Arabs.
Although there are few texts referring to the obscure beginnings of Hatra, it seems that a smallish Assyrian settlement grew up in the 3rd century BC becoming a fortress and a trading centre. Founded by nomadic horsemen from a Khorasan tribe, the Parthian empire of the Arsacid dynasty (247 BC-AD 226) claimed to be the successor of the Achaemenid Empire of Cyrus. In the 2nd century BC, it flourished as a major staging-post on the famous oriental silk road to become another of the great Arab cities as Palmyra in Syria, Petra in Jordan, and Baalbek in Lebanon. This Eastern monarchy was a source of concern for the Romans who sought unsuccessfully to destroy it.
With this historical background, the site of Hatra, a large fortified city, the remains of which are to be seen in the middle of the desert 110km south-west of Mosul, can be taken as a symbol of the struggles which opposed Parthians and Romans for the spoils of the old empire of Alexander.
The city was seized unsuccessfully in 116 by Trajan (who died in Cilicia the following year); again it resisted Septimius Severus in 198 who, however, after having taken Ctesiphon and annexed Mesopotamia was acclaimed in Rome with the title of Parthicus Maximus. Some architecture and some inscriptions seem to point to a form of Roman occupation or of a Romano-Hatrene alliance in the AD 230s and inscriptions point to the rule of emperor Gordian III. Hatra could therefore be seen as the furthest extent of the empire at that time. Shortly thereafter Hatra was destroyed by Ardashir I (226-42), the founder of the Sassanid dynasty.
The present-day remains date back to between the 1st century BC and the 2nd century AD. The remains of the city, especially the temples where Hellenistic and Roman architecture blend with Eastern decorative features, attest to the greatness of its civilization. The fortifications were immense: the city's defences are comprised of two walls which separate a wide ditch. The external wall is an earthen bank; the inner wall is built from stone and has four fortified gates which roughly correspond to the four cardinal points. In the heart of this round city of almost 2 km in diameter, a rectangular temenos lies in an east-west direction. It is surrounded by a stone wall interrupted by towers. A north-south wall divides it into two unequal spaces. The function of this temenos - where there is a heavier concentration of temples in the west space - seems to have been both religious and commercial: shops looking on to a pilastered portico have been found on each of the four sides of the rectangle.
In the very centre of Hatra lies the temple complex dedicated to several Hatrene gods, the chief of which was the Sun god Shamash. Around 156, Hatra was governed by Arab rulers: prominent among them was Nasr, father of the first two kings of Hatra: Lajash and Sanatruq. The latter completed the Temple of Shamash, Sculptures have been discovered to Apollo (Balmarin in the Hatrene religion), Poseidon, Eros, Hermes, Tyche (the guardian goddess of Hatra) and Fortuna.