THE dominant theme in the history of thirteenth-century Europe is arguably that of expansion: the expansion of Latin Christendom, to encompass Orthodox, Muslim and pagan lands previously on its outer fringes; the expansion of the economy, as western merchants (Italian, German, Catalan) penetrated deeper into the Mediterranean, the Baltic and the European land mass; the expansion too of population, to which a halt was called only around 1300; the expansion also of government, as rulers in western Europe consolidated their hold over their territories, and as the papacy made consistent claims to its own authority even over secular rulers. By the end of the thirteenth century the political and demographic expansion of powerful European kingdoms could be felt, too, on the edges of the British Isles, as the English king posed an ever sharper threat to the autonomy of the Welsh princes and the Scottish kings. To see the thirteenth century in this light is not simply to see it from a western, Latin, perspective. It will be obvious already that a major feature of the period is the encroachment of the Latin west upon the Greek and Slavonic east, as upon the Muslim world: this was the era of major crusades, under royal and princely direction, against Egypt, Tunis, Muslim Spain and indeed pagan Prussia and Livonia, but it was also the period in which a diverted crusade, aiming originally at the mouth of the Nile, found itself able to overwhelm Constantinople, fragmenting the already fragile Byzantine empire and imposing (not very successfully) the authority of the bishop of Rome over the Orthodox Church in Greece. Nowhere in Europe, nor indeed in the Mediterranean, were the Latins totally invisible. Even if it were not the case that the history of medieval Europe can only be written after paying attention to the east of Europe (including Byzantium), and the Islamic lands bordering on Europe, it is hard to see how a volume on the thirteenth century could lack detailed attention to areas far from the Ile-de-France, and issues remote from the conflict of popes and emperors, the theme that has dominated many surveys of this period.