The Seleucid Empire was a superpower of the Hellenistic Age, the largest and most powerful of the Successor States, and it's army was central to the maintenance of that power. Antiochus III campaigned, generally successfully, from the Mediterranean to India, earning the sobriquet 'the Great'.

Jean Charl Du Plessis has produced the most in depth study available in English devoted to the troop types, weapons and armor of Antiochus' army. He combines the most recent historical research and latest archaeological evidence with a strong element of reconstructive archaeology, that is the making and using of replica equipment.

Sections cover the regular, Hellenistic-style core of the army, the auxiliaries from across the Empire and mercenaries, as well as the terror weapons of elephants and scythed chariots. Weapons and armor considered in great detail, including, for example, useful data on the performance of slings and the wounds they could inflict, drawing on modern testing and the author's own experience.

The army's performance in its many battles, sieges and campaigns is analyzed and assessed.