Battle of Magnesia

The Roman–Seleucid War battle fought near Magnesia ad Sipylum in 190 or 189 BCE, in which Roman and Pergamene forces defeated Antiochus III’s army.

Roman legion: The principal military unit of the Roman army, organized into cohorts and centuries. Roman infantry formations helped hold the line against Antiochus III’s larger army.
Roman–Seleucid War: A war between the Roman Republic and the Seleucid Empire, fought from 192 to 188 BCE. Magnesia was the decisive land battle of this wider conflict.
Treaty of Apamea: The 188 BCE treaty that ended the Roman–Seleucid War and imposed territorial and military restrictions on the Seleucid Empire. It formalized the settlement imposed after the Roman victory at Magnesia.
Livy: A Roman historian who wrote a broad history of Rome from its legendary origins through the late Republic. His account preserves a detailed narrative of the Roman campaign and battle.
Antiochus III the Great: A Seleucid king who expanded his empire across western Asia and fought Rome in the Roman–Seleucid War. He commanded the Seleucid army and chose the ground for the battle.
Antiochus III's invasion of Greece: Antiochus III’s military campaign in Greece beginning in 192 BCE, which brought him into direct conflict with Rome. The invasion prompted Rome to carry the war into Seleucid territory.
Seleucid Empire: A Hellenistic empire founded by Seleucus I, stretching at its height from Asia Minor to regions east of Iran. The empire survived Magnesia but lost much of its western territory and strategic reach.
Appian: A Greek historian of the second century CE who wrote a history of Rome’s wars. His account offers a separate narrative of the Roman–Seleucid conflict.
Seleucid army: The military forces maintained by the Seleucid Empire, combining Macedonian-style infantry with troops from across its territories. Its diverse units and war elephants shaped the battle’s opening and eventual collapse.
Aetolian League: A federation of Greek communities that opposed Macedonian and Roman power at different points in the Hellenistic period. Its invitation to Antiochus III helped trigger Rome’s war against the Seleucids.

Linked from 13 pages