PARIS IN THE nineteenth century was a world city. Offering a hypnotic combination of freedom, pleasure and modernity, it defined itself as cosmopolitan by nature. Contemporary French books called it 'the city of foreigners par excellence', 'the great European city par excellence': the real foreigner in Paris was the native " Parisian. One in ten Parisians, in the years between 1830 and 1870, was a foreigner. For Italians and Germans, Paris was the capital of freedom and ideas (and, in many cases, the best market for their talents): Marx became Marxist, and met Engels, while living in Paris in 1844-5. For the English, Paris was a capital of pleasure, and low prices. The nation for whom Paris was most important, however, and the nation which won the greatest ascendancy over Parisian hearts and minds, was Poland.In both the eighteenth and the twentieth centuries Parisians were relatively indifferent to the fate of Poland. In the years from 1830 to 1870, however, a common Catholicism, a common liberalism and I above all the contribution to French Chopin: exquisite victories of Polish soldiers serving in French