Defence in depth in order to retreat successfully, and they assume that the defender's morale will recover from the retreat. A possible early example of this came at the Battle of Cannae in 216 BC, when Hannibal employed this manoeuvre in order to encircle and destroy eight Roman legions, but that is disputed by some historians. Edward Luttwak used the term to describe his theory of the defensive strategy employed by the Late Roman army in the 3rd and 4th centuries AD. Later examples of defence in depth might be European hill forts and the development of concentric castles. In those examples, the
Ancient history not to be confused with "Classical Antiquity". The term classical antiquity is often used to refer to Western History in the Ancient Mediterranean from the beginning of recorded Greek history in 776 BC (First Olympiad). This roughly coincides with the traditional date of the founding of Rome in 753 BC, the beginning of the history of ancient Rome, and the beginning of the Archaic period in Ancient Greece. The academic term "history" is additionally not to be confused with colloquial references to times past. History is fundamentally the study of the past through documents, and can be either scientific (archaeology)