THE MISSIONARIES: AUGUSTINE, AIDAN, WILLIBRORD, BONIFACE
The transformation of Christianity from a Mediterranean to a European religion was slow and gradual; the years of unsettlement during the barbarian invasions were not favourable to missionary progress. Some of the new nations had received the Arian form of Christianity from the labours of Ulfilas, before they had set out on their wanderings; others, like the Anglo-Saxons in Britain, conquered and settled as heathen. The Franks had been baptised, with Clovis their king, to orthodox Christianity: the monks of Columbanus taught the heathen on their borders, and the Frankish bishops, like Gregory of Tours, tried to consolidate their position in northern France by building outlying churches and chapels. When Gregory the Great began his pontificate, however, the Anglo-Saxons had driven British Christianity back into Brittany, Cornwall, Wales and Strathclyde; and central Europe was heathen from the regions now known as Belgium, north-east France, and Alsace-Lorraine, across to where in the Balkans the east Roman emperors strove to protect Greek Christianity from the heathen invaders. The Christianity of the old Roman empire in the intermediate region, in the provinces of the Rhine and the Danube, had been wiped out: and even the Christianity planted by Ulfilas in Roumania and the later Bulgaria had perished, or passed
with the migrating Goths into western Europe. The conversion of the northern two-thirds of Europe was to be slow: that of Sweden was not begun till the ninth century, that of Norway not till the tenth.