Early Nordic co-operation
There are numerous theories in history about the first signs of organized co-operation in the Nordic region. One claims it was a treaty signed by Denmark, Norway and Sweden in 1397, called the Kalmar Treaty. Through inheritance and family ties the three countries had been united under the rule of the Danish Queen Margareta. This treaty united the three countries into one front with one head of state, leaving each country responsible for home affairs according to their rules and laws. At least in Sweden, the whole period was marked by conflict between the monarch and nobility on one hand and the burghers and peasants on the other, which culminated in a rebellion in 1452, when Gustav Vasa was elected King.