Introduction

Many mathematicians, and scientists in general, have worked extensively in countries other than those of their origin. The reasons may have been, in different periods, political or economic. The lack of suitable employment opportunities in their countries, the adverse political systems and wars have often led to the emigration of scientists who played an important role in spreading scientific knowledge. This phenomenon has been recurrent in past centuries. The present volume aims to analyse, starting from particular cases, the situations that have changed the scientific landscape, the tradition and the very future of studies and research. Although one focus of investigation concerns personal motivations, often little known, and the political and social circumstances that determined the migrations, and their effect on the scientific careers of the protagonists, of no less importance are the repercussions that these migrations have had in regard to scientific progress in the countries of both origin and arrival. The topics covered irange from the eighteenth century to the period of the Second World War and concentrate, in particular, on Euler, Lagrange and Boscovich’s scientific biographies, emigrations of scientists from France, Spain and Greece to Russia in the eighteenth and nineteenth centuries, and from Russia to France in the twentieth century, exiles from Italy before the Italian Risorgimento, migrations inside Europe, and the escape overseas of mathematicians from Nazi and Fascist regimes between the two World Wars, and the mobility of experts around the world.