Answer
Expanding his territories, Antiochus III aimed to restore the Seleucid Empire to its former glory. He engaged in extensive military campaigns, successfully securing control over several regions. His conquests included parts of Asia Minor, the Levant, and areas within modern-day Iran and Afghanistan. By achieving these territorial gains, Antiochus III significantly enlarged the boundaries of the Seleucid Empire and bolstered its power and influence in the region.