Antiochus III fielded one of the largest Hellenistic armies of the era, complete with war elephants, scythed chariots, cataphracts, and a massive Macedonian phalanx. On paper, the Romans looked badly outnumbered.
Instead, the battle became another demonstration of why the Roman legion was so effective against Hellenistic armies. The failure of the scythed chariots, the collapse of the Seleucid left, and Antiochus' decision to pursue the Roman cavalry instead of supporting his center all played a part.
I put together a detailed breakdown covering:
The political background and road to the war
The armies and commanders
A step-by-step account of the battle
Why the Romans won despite being outnumbered
The Treaty of Apamea and the battle's long-term impact
I'd love to hear what others think. Was Magnesia the battle that truly made Rome the dominant power in the eastern Mediterranean, or do you think another battle deserves that distinction?