|Battle of the Harpasus|
|Kingdom of Pergamon||Seleucid Empire|
|Commanders and leaders|
|Attalus I||Antiochus Hierax|
The Battle of the Harpasus was fought in 229 BC between the Pergamese and Seleucid armies on the banks of the Harpasus River, a tributary of the Maeander River in Caria. The battle on the Harpasus was the last battle of the war between King Attalus I of Pergamon and the Seleucid prince Antiochus Hierax over dominion of western Anatolia. Attalus won a decisive victory and Hierax started a failed campaign in Mesopotamia that would lead to his defeat and later death at Egypt.
- Jaques 2007, p. 436
- Jaques, Tony (2007). Dictionary of Battles and Sieges. Greenwood Publishing Group. ISBN 978-0-313-33538-9.