This book offers the first systematic, comparative analysis of the ideology of kingship and empire under the Achaemenids, Alexander the Great and the early Seleucids. It explores key issues thematically such as legitimation, representations of empire and royal space. Through this method, Stephen Harrison breaks traditional periodisation offering new insights into long-term trends. The book challenges existing narratives about the relationship between the Achaemenids and their successors. Rather than focusing on the mere facts of continuity and change, the study advocates for a more complex understanding of the Achaemenids' impact on monarchical ideology under Alexander and the Seleucids. Harrison's comparative approach brings the three empires into dialogue with one another and thus treats them all equally through this lens. The methodology highlights the uniqueness of particular strategies deployed by different rulers and isolate ideas which were distinctively 'Achaemenid', 'Alexandrine' or 'Seleucid' as opposed merely to identifying monarchical commonalities.