The Seleucids were led by Antiochus III the Great, who launched an invasion of Bactria to recover his ancestor's past dominions.

The Seleucids had advanced into the Greco-Bactrian territory as part of an expedition to gain back the land they had lost after Antiochus II's death.

Getting wind of this, Euthydemus was soon on hand leading 10,000 cataphracts, after marching for three days from Tapuria to meet the Seleucid army.

Antiochus had received word that the Bactrians would guard the river throughout the day, but when it became night, they retired to a city twenty stadia off.

[6] Meanwhile, as Panaetolus countered the Bactrians, Antiochus regrouped what remained of his cavalry and took many prisoners, later withdrawing to the other side of the river.