Antiochus III (Antiochus the Great), d. 187 B.C., king of Syria (223-187 B.C.), son of Seleucus II and younger brother of Seleucus III, whom he succeeded. At his accession the Seleucid empire was in decline. Although Antiochus did not succeed in totally restoring the greatness of the Seleucid dynasty, he did much to revive its glory. He led an expedition (212-205 B.C.) to the eastern provinces and went as far as India. Although he was defeated earlier by the Egyptians at Raphia (modern Rafa), he and Philip V of Macedon undertook (202 B.C.) to wrest Egyptian territories from the boy king, Ptolemy V. Antiochus did not properly appreciate the growing power of Rome. While Philip V was engaged by the Roman armies, Antiochus recovered S Syria and Asia Minor. In 199 he won a decisive victory over the Egyptians; Palestine then reverted to Syria, having been under Egyptian rule for almost a century. In 196 he seized the Thracian Chersonese and thus alarmed the Greeks. They as well as the Egyptians sought the aid of the Romans. Antiochus, who disregarded the advice of Hannibal in 193, waited and then challenged Rome by accepting the invitation of the Aetolian League to interfere in Greece in 192. The Romans crushed him (191) at Thermopylae and again at Magnesia (190). He also lost a number of naval engagements, and in 188 he was forced to give up all his territory W of the Taurus. Thus the Seleucid empire became a purely inland Asian state, and dreams of reviving Alexander's empire died.

known as Antiochus the Great

(born 242—died 187 BC, near Susa, Iran) Seleucid king of the Syrian empire (223–187 BC). After quelling a rebellion by Achaeus, his governor in Asia Minor (213), Antiochus marched east to India (212–205). He forged a peaceful alliance with Armenia and forcible ones with Parthia and Bactria, stilling resistance to his campaign. After the death of Ptolemy IV, Antiochus and Philip V of Macedonia divided most of his empire, Antiochus taking the southern and eastern lands, including Palestine (circa 202). He then marched against Egypt, concluding a peace in 195, through which he acquired southern Syria and Ptolemy's territories in Asia Minor. Rome grew angry with Antiochus after he admitted Hannibal of Carthage to his court; when Antiochus took a force to defend the Aetolians against Rome, Rome struck against him, eventually defeating him at Magnesia (189). He gave up lands in Europe and western Asia Minor but kept Syria, Mesopotamia, and western Iran. He was murdered while exacting much-needed tribute near Susa.

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