If you want a history of the countries surrounding the mediterranean, who did what, who was bad who was good, then JJ Norwich’s book is very entertaining, as indeed are all of his.  I was expecting something along the lines of Ferdinand Braudel’s great work ‘ The Mediterranean and the Mediterranean World in the Age of Philip II‘ which ranges backwards and forwards as necessary, but covers the sea’s geography, its environment, its peoples, its trade, its communications, its climate, its cities…wonderful, wonderful stuff, masterful, and recognised by all major historians as  one of the great histories. But John Julius Norwich’s book in comparison is much more a good read and good fun for dipping into. It’s your choice!