Antiochus III the Great (
Greek: ; c. 241 – 187 BC, ruled 222–187 BC) was a
Hellenistic Greek king and the 6th ruler of the
Seleucid Empire. He ruled over the
region of Syria and large parts of the rest of
western Asia towards the end of the 3rd century BC. Rising to the throne at the age of eighteen in 222 BC, his early campaigns against the
Ptolemaic Kingdom were unsuccessful, but in the following years Antiochus gained several military victories and substantially expanded the empire's territory. His traditional designation,
the Great, reflects an epithet he assumed. He also assumed the title
Basileus Megas (Greek for "Great King"), the
traditional title of the Persian kings. A militarily active ruler, Antiochus restored much of the territory of the Seleucid Empire, before suffering a serious setback, towards the end of his reign, in his war against Rome.