The year 1130 represented a watershed in Norwegian history. A period of peace was disrupted by conflict and civil war lasting until 1227.
But 1130 was a special year in other ways too. It is regarded as the start of the High Middle Ages, a period of population growth, consolidation within the Church, and the emergence and development of townships. As the Crown and Church brought district after district under their rule, the degree of public administration and authority increased. According to modern historians, it is first during this process that Norway could be termed a single realm.
The power of the monarchy increased in the 1100s and 1200s, ending in victory over both the Church and the feudal lords. The traditional secular aristocracy was replaced by a serving aristocracy. The status of the peasant farmers changed in this period, from that of freeholder to that of tenant. However, peasant farmers in Norway usually rented their land on a lifetime basis, and thus enjoyed a free status that was rare in most of contemporary Europe. The slaves of the Viking Age also disappeared in the High Middle Ages.
During this period the political centre of gravity in Norway shifted from the southwest to the districts surrounding the Oslo Fjord. During the reign of King Haakon V, in the 1200s, Oslo became Norway's capital. Prior to this it had been an insignificant clutch of houses in the innermost reaches of the Oslo Fjord. When the Black Death reached Norway, in 1350, the town allegedly housed no more than 2,000 people. At that time Bergen had a population of 7,000 and Trondheim 3,000.
The state revenues in the High Middle Ages were extremely modest by European standards. Towards the end of the period they were scarcely adequate to finance any expansion of the administrative apparatus of Crown and state. The plague had raged with terrible effect, reducing the population to one-half or even one-third of its pre-1350 level. This prompted the King and the nobility to seek revenues from lands and feudal estates, regardless of national boundaries, and contributed towards the growth of the political unions in the Nordic lands.
From 1319 to 1343, Norway and Sweden shared a joint monarchy, an institution later expanded through the arrangement of inter-Scandinavian royal marriages. Haakon VI (1340-80) – son of Swedish King Magnus Eriksson, and Ingebjørg, daughter of Haakon V – was lawful heir to the throne of Norway. He married Margrete, daughter of Danish King Valdemar Atterdag. Their son, Olav, was chosen to be Danish king on the death of Valdemar in 1375. Olav also inherited the throne of Norway after his father in 1380, thus bringing Norway into a union with Denmark which lasted right up to 1814.
The Advent of Christianity
Christianity was introduced into Norway over a lengthy period of time, possibly two hundred years. It was a natural result of the Norwegians' contact with Christian Europe, through trading connections and Viking raids. Missionaries from the churches of England, Germany and Denmark contributed to a weakening of traditional belief in the Nordic gods. This development culminated with the three missionary kings, Haakon the Good, Olaf Trygvasson, and Olaf Haraldsson (Olaf the Stout). The latter's death as a martyr at the battle of Stiklestad in 1030 gave him status as a saint. The Church won the final victory.
From the middle of the 11th century the legislation that was enacted, the songs that were sung, and the monuments that were erected demonstrated the firm establishment of Christianity in Norway. Shortly before the year 1100 the first bishoprics appeared, among them the see of Nidaros, later Trondheim, where the archbishop held office from 1152. The Norwegian archbishop also played a political role. In 1537 the Reformation was enforced in Norway by royal decree. At this time the country was under Danish rule, and the Reformation was enforced simply by applying the Dano-Norwegian church ordinance in Norway as well. From the early 1600s the Lutheran creed was the sole creed of Norway.