The city continued to flourish under Parthian rule beginning in 141 BC; ancient texts claim that it reached a population of 600,000.

Seleucia was destroyed in 165 AD by Roman general Avidius Cassius and gradually faded into obscurity in the subsequent centuries.

Seleucia (Ancient Greek: Σελεύκεια, Seleúkeia) is named for Seleucus I Nicator, who enlarged an earlier settlement and made it the capital of his empire around 305 BC.

Although Seleucus soon moved his main capital to Antioch, in northern Syria, Seleucia became an important center of trade, Hellenistic culture, and regional government under the Seleucids.

To make his capital into a metropolis, Seleucus forced almost all inhabitants of Babylon, except the local temple priests/supporting workers, to leave and resettle in Seleucia.

A tablet dated 275 BC states that the inhabitants of Babylon were transported to Seleucia, where a palace and a temple (Esagila) were built.

Standing at the confluence of the Tigris River with a major canal from the Euphrates, Seleucia was placed to receive traffic from both great waterways.

During the 3rd and 2nd centuries BC, it was one of the great Hellenistic cities, comparable to Alexandria in Egypt, and greater than Syrian Antioch.

Excavations indicate that the walls of the city enclosed an area of at least 550 hectares (1,400 acres), equivalent to a square roughly 1.5 miles (2.5 kilometers) on a side.

The Synod of Dadyeshu decided that the Catholicos should be the sole head of the Church of the East and that no ecclesiastical authority should be acknowledged above him.

[8] [9] [10] Finds included many coins, mostly bronze, salt receipts with the name of Seleucia, a blue glazed incense burner, now in the Baghdad museum, a stele inscribed in Greek, numerous beads, metal objects including weights and surgeons instruments, and one pre-Sargonic brick.

[11] From 1964 to 1968 and then between 1985 and 1989, an Italian mission from the University of Turin directed by Antonio Invernizzi and Giorgio Gullini excavated at the site.