Seleucia emerged from the ashes of Babylon around 305 BC when Seleucus I Nicator ordered a massive population transfer. He forced almost all inhabitants of Babylon to leave their ancient homes and resettle in this new city on the west bank of the Tigris River. Only local temple priests and supporting workers were exempted from the decree. A tablet dated 275 BC confirms that these displaced people were transported to build a palace and construct a temple named Esagila within the new walls. The site sat at the confluence of the Tigris River with a major canal from the Euphrates, positioning it to receive traffic from both great waterways. Seleucus enlarged an earlier settlement to create his first capital before eventually moving the imperial seat to Antioch in northern Syria.
Hellenistic Trade And Population
Archaeological excavations reveal that the city walls enclosed an area of at least one square mile, roughly 1.5 miles or 2.5 kilometers on each side. This vast perimeter suggests an initial population exceeding 100,000 residents, potentially growing much larger over time. Ancient texts claim the metropolis reached a staggering figure of 600,000 inhabitants during its peak. Polybius used the term Macedonian peliganes for the council of Seleucia, implying a colony consistent with its rise under Seleucus I. Pausanias recorded that Seleucus also settled Babylonians there alongside Greek colonists. Excavations indicate the presence of a large population not entirely defined by Greek culture alone. The surrounding region might have supported half a million people living in the shadow of these massive fortifications.Parthian Conquest And Rule
Mithridates I conquered the city in 141 BC and made it the western capital of the Parthian Empire. Tacitus described the walls and noted that Seleucia remained a fully Hellenistic city even under new Parthian administration. A senate of 300 people ruled the city while ancient sources claimed 600,000 inhabitants lived within its bounds. In 55 BC, a crucial battle near Seleucia established dynastic succession among the Arsacid kings. The reigning Mithridates III fought against Orodes II with support from a Roman army led by Aulus Gabinius. A massacre of around 5,000 Babylonian Jewish refugees occurred at Seleucia in 41 BC according to Josephus. Tetradrachms minted by Mithridates I bear inscriptions showing the blend of cultures during this era.