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
Sexuality in ancient Rome reviled throughout Latin literature. In general the Romans had more flexible gender categories than the ancient Greeks. A late 20th-century paradigm analyzed Roman sexuality in terms of a "penetrator–penetrated" binary model, a misleadingly rigid analysis that may obscure expressions of sexuality among individual Romans. Even the relevance of the word "sexuality" to ancient Roman culture has been disputed, but in the absence of any other label for "the cultural interpretation of erotic experience", the term continues to be used. Ancient literature pertaining to Roman sexuality falls mainly into four categories: legal texts; medical texts; poetry; and political discourse. Forms of