Answer
Antiochus III ascended to the throne at the tender age of 18. He was born in 242 BC and inherited the Seleucid throne upon the death of his father, Seleucus II Callinicus, in 223 BC. Upon assuming power, Antiochus III was faced with a formidable challenge of restoring Seleucid dominance in a turbulent era marked by territorial disputes and rivalries.