The Argentine tango, as a dance and as an irresistible musical form that later became paramount in Argentine popular taste during its legendary 'golden age' between 1920 and 1950, first acquired world-wide fame in the years after 1913 - the moment of its spectacular triumphs in high-society Europe. As a social craze, especially but not exclusively among the European upper and middle classes, it had few equals in the period just before the First World War. The tango's popularity on the dance-floors of Europe and North America held until at least the end of the 1930s. Its history was by no means over in 1913 - indeed, from a musical viewpoint it was only just starting. Yet it is also true that the frenzied episodes of 'tangomania' in Europe during 'the tango year' (as H. G. Wells called it soon afterwards) marked the culmination of a story whose opening was far removed from the elegant salons and hotels of Paris and London. Whatever it may have become, the tango had roots that were quintessentially popular. When, where and how did it originate? None of these questions can be answered with absolute precision. Pieces are missing from the jigsaw and are unlikely to be found at this stage. When? The date conventionally given, 1880, can be no more than approximate. The tango's genesis was not instantaneous: its development into anything like a recognizable form (a form undergoing several significant modifications thereafter) occurred over a number of years, the critical phase almost certainly falling between 1880 and the middle 1890s. But no exact chronology of the tango's 'foundational era' can be established easily. Where? We can be rather more definite on this score. There is no real doubt that the port-city of Buenos Aires was the birthplace of the dance. The city's arrabales (poor outer districts) were probably the key location. It must also be noted, however, that the tango also took root very early on in Montevideo, the other River Plate capital. This explains the claims (which certainly cannot be dismissed too readily) of a parallel development having taken place on both sides of the great