More recently, the Mediterranean has become the theatre in which many migrants from sub-Saharan Africa have tried, often at the risk of their lives, to enter the wealthy lands of the European Union, and this wave of migration has been compounded by migration out of North Africa, particularly Libya, during the current upheavals, as well as migration into the Aegean and beyond from the hinterland of western Asia. Although the main target of these migrants is often European lands north of the Mediterranean, the settlement of a great many of them in Italy, Spain and other Mediterranean states has had a powerful impact on social relations within those countries. 

And then of course there is another type of migration, temporary but transformative: people from northern Europe and elsewhere converging on the Mediterranean in search of summer sun, a mass phenomenon of the late 20th century that has transformed the local industries, the labour market, the physical appearance, even the social and cultural norms, of towns and villages along virtually the entire Mediterranean coastline of Spain, France and Italy, and increasingly in Turkey, Tunisia and other Mediterranean lands. 

What we see is a heavy interdependence between the tourist industry and the economies of northern Europe, injecting a further element of fragility into the economy of most Mediterranean countries, particularly at times of political upheaval, when popular destinations are suddenly rendered inaccessible, as happened to the coast of Yugoslavia during the break-up of that country.   

The conflict in former Yugoslavia reminds us that the Mediterranean world has seen both the reasonably peaceful coexistence of peoples and religions, and the violent collapse of that coexistence.  Port cities in particular acted as hosts to mixed populations of Christians, Jews and Muslims, of all sorts of origins.  

The extreme case of a cosmopolitan eastern Mediterranean city is Alexandria, ever since its foundation by Alexander the Great in the fourth century BC. Early in the 20th century, Europeans accounted for only 15 per cent of the population, even if it was they who exercised most of the economic power; in 1927 there were about 49,000 Greeks in the city and 24,000 Italians. Overlapping with various nationalities there were 25,000 Jews. The majority of influential Muslim families, including the royal family, hailed from Turkey, Albania, Syria or Lebanon. They, as much as the settlers of European descent, wished to identify strongly with European, particularly French, culture.