of plagues such as the world had not seen since the sixth century and was not destined to see again till the 1890s." It was actually three related diseases: bubonic plague and septicaemic plague, carried by fleas hosted by the black rat, and pneumonic plague, the especially fast and lethal airborne variant. The few areas that escaped included Poland, Hungary, Rouergue in France, Liège in Belgium, and the county of Béarn in the Pyrenees. It has been suggested that these areas were spared due to the predominance of O-Blood type, which had only recently taken root in the heartlands of Europe, although this hypothesis has yet to be proven. The pandemic, which began in central Asia, was first reported in Europe in the summer of 1346. The Genoese colony of Caffa in the Crimea was besieged by the Tartars, who catapulted plague-ridden corpses into the city. The defenders carried the disease back to Italy; in October 1347 it reached Messina in Sicily, in December a ship carried the plague into Marseille, and by January 1348 it was in Genoa. The plague then moved northward through France. According to the French monk Guillaume de Nangis: The reasons for the plague's success are not yet entirely understood. Urban overcrowding, declining sanitary conditions and the "lively European trade in (rat-infested) grain" have been cited as causes of the plague's rapid transmission; while favourable climatic conditions and the summer months may also have aided its spread. In the summer of 1348 it reached England, arriving first at Melcombe Regis in Dorset. It had spread through the southwestern shires to London by winter. It peaked in the summer of 1349, when it was passed on into Germany and Austria, and in winter it was in Scotland, Scandinavia and Spain. In general, towns were hit more severely than rural areas, the poor more than the rich, and the young and fit more than the old and infirm. Norman Davies generalises that "No pope, no kings were stricken." Hundreds died in each parish, although some figures may have been exaggerated. Norwich, a city that did not exceed 17,000, was reported as having lost 57,000. The Italian humanist Giovanni Boccaccio records a loss of 100,000 in Florence, exceeding the total population of the city. The figure was probably closer to 50,000. Regardless, modern studies make it clear that the plague's toll in this decade was heavy. Heaviest hit