The Swedish settlers moved to the area from Svealand, southern Norrland and Götaland in the late 13th century, and therefore the population increased remarkably. About half of the villages in the current National Park cooperation area were inhabited already in the Middle Ages. The population in the archipelago increased until the mid 16th century, after which it started to decline rapidly. The natural resources could not support more people with the techniques of the time. The decline was caused not only by the decrease in available natural resources but also by wars and diseases. In the beginning of the 18th century the Great Northern War and the Black Death made the life more difficult in the archipelago.