Euthydemus was defeated by Antiochus at the Battle of the Arius .
After sustaining a famous siege in Antiochus ' capital Bactra ( Balkh ) , Antiochus obtained an honourable peace by which Antiochus promised Euthydemus ' son Demetrius the hand of one Antiochus ' his daughters .
Euthydemus was defeated by Antiochus at the Battle of the Arius but after sustaining a famous siege in his capital Bactra ( Balkh ) , he obtained an honourable peace by which Antiochus promised Euthydemus ' son Demetrius the hand of one of his daughters .