Although the Nordic Region was part of Christian Europe, it retained certain distinctive features.

Its social structure was not very complicated. The peasantry made up the overwhelming majority of the population, the social elite were few in number and the kings had little real administrative power. There was no professional military and there were almost no towns.

The Nordic Region gradually became more like the rest of Europe over the course of the Middle Ages.

The Crown strengthened its position in the 12th and 13th centuries through imposing taxes on farms. The great men of the nation could exempt themselves from taxation by doing military service on behalf of the king.

A class of nobles was therefore created, one whose power was based on horsemanship and skill in battle, ownership of farms, taxation of the peasantry and ruling kingdoms along with their monarch.

The Hanseatic League creates a trading network

In the Viking era, chiefs acted as traders, carrying goods on their longboats. In the 12th and 13th centuries, the boom in European long-distance trading, which had begun in the Mediterranean some centuries before, reached the Nordic Region.

The German merchants who formed the Hanseatic League served as intermediaries. Lübeck on the German Baltic Sea coast became a major commercial and political centre in the Nordic Region.

Many new towns were founded in the south and middle of the Region. Raw materials such as timber, iron and fur were exported, while dry goods and salt were imported from the Continent.

From three kingdoms to the Kalmar Union

Politically, the three kingdoms were closely interwoven – the royal families interbred, entered into alliances and fought each other in numerous wars.

Both the Danes and the Swedes embarked upon lengthy crusades against the pagan peoples of the Baltic's southern and eastern coasts. At its peak, Denmark's territory stretched as far as modern-day Estonia.

For a brief period in the 14th century, Norway, Sweden and the Scanian provinces were ruled over by the same king.

From the late 14th until the early 16th century, the whole region was united as the Kalmar Union. This was a loose union in which each kingdom retained its own laws and was ruled by its native elite.

This was typical of unions in Europe at the time, such as Poland–Lithuania and Castilia–Aragon (Spain). However, unlike these, the Kalmar Union did not evolve into a permanent state.

As was common at the time, the Kalmar monarchs did try to extend their power, but met with resistance from the aristocracy and church leaders. The peasants also revolted against tax increases. Sweden effectively remained outside the union for long periods.

Although it was envisaged as bringing peace to the Nordic Region, in reality the Kalmar Union led to constant civil war. It finally collapsed after a series of crises and disputes about royal succession at the start of the 16th century.