The great trading nation of Argos has the busiest port of the Hyborian Age, Messantia as it's capital. King of Kings Kumbaniash, ruler of Shem has long envied Argos' wealth and seeks to bring it under his control. He would then have a network of trade from Cathay to Kush which would bring wealth and power beyond compare.
As Aquilonia is engaged in Zingara he unleashes his host upon Argos.
As the Shemites assail the eastern provinces with fire and sword King Milo V prepares to confront an army that has defeated half the world. His professional army is small but augmented with barbarian mercenaries and war elephants from Kush.
The Argosseans are in red at the top of the picture.
King Milo advances as his slingers damage the Kothian chariots.
Then his warriors attack the Shemite archers who evade to avoid harm.
The infantry battle ebbs and flows.Kumbaniash charges in to protect his infantry flank but is eventually defeated and is forced to take refuge amidst his bowmen.
The Shemites respond by darkening the sky and the barbarian warriors are destroyed.
After the retreat to Asgalun the Shemites sue for peace. Koth, Ophir and Turan declare independence and King of Kings Kumbaniash is murdered by his generals.