he united under his rule, and Viking rule in Ireland ended as well. In Normandy the Vikings adopted French culture and language, became Christians and were absorbed into the native population. By the beginning of the 11th century Scandinavia was divided into three kingdoms, Norway, Sweden, and Denmark, all of which were Christian and part of Western civilization. Norse explorers reached Iceland, Greenland, and even North America, however only Iceland was permanently settled by the Norse. A period of warm temperatures from around 1000–1200 enabled the establishment of a Norse outpost in Greenland in 985, which survived for some 400 years as the most westerly outpost of Christendom. From here, Norseman attempted their short-lived European colony in North America, five centuries before Columbus. In the 10th century another marauding group of warriors swept through Europe, the Magyars. They eventually settled in what is today Hungary, converted to Christianity and became the ancestors of the Hungarian people. A West Slavic people, the Poles, formed a unified state by the 10th century and having adopted Christianity also in the 10th century but with pagan rising in the 11th century. By the start of the second millennium AD, the West had become divided linguistically into three major groups. The Romance languages, based on Latin, the language of the Romans, the Germanic languages, and the Celtic languages. The most widely spoken Romance languages were French, Italian, Portuguese and Spanish. Four widely spoken Germanic languages were English, German, Dutch, and Danish. Irish and Scots Gaelic were two widely spoken Celtic languages in the British Isles. High Middle Ages: 1000–1300 Art historian Kenneth Clark wrote that Western Europe's first "great age of civilisation" was ready to begin around the year 1000. From 1100, he wrote: "every branch of life – action, philosophy, organisation, technology [experienced an] extraordinary outpouring of energy, an intensification of existence". Upon this period rests the foundations of many of Europe's subsequent achievements. By Clark's account, the Catholic Church was very powerful, essentially internationalist and democratic in its structures and run by monastic organisations generally following the Rule of Saint Benedict. Men of intelligence usually joined religious orders and those of intellectual, administrative or diplomatic skill could advance beyond the usual restraints of society – leading churchmen from faraway lands were accepted in local bishoprics, linking European thought across wide distances. Complexes like the Abbey of Cluny became vibrant centres with dependencies spread