During the Folkung Dynasty, in the fourteenth century, the royal
houses of Sweden and Norway became united through the marriage of Duke
Eric, of Sweden, and Ingeborg, only child of King Haakon, of Norway;
and Duke Valdemar to the king's niece of the same name. In May, 1319,
King Haakon died, and Magnus Ericsson, the young son of Duke Eric and
Princess Ingeborg, inherited the crown of Norway, and July 8 of the
same year was elected King of Sweden, at Mora in Upland.

For the attainment of this end, Magnus' mother, Duchess Ingeborg, and
seven Swedish councillors had worked with great activity. They had
taken part in shaping the first Act of Union of the North in June,
1319, and from Oslo, in Norway, hastened to have Magnus elected at
the Stone of Mora, where the Swedish kings since time immemorial were
nominated. The Act of Union stipulated that the two kingdoms were to
remain perfectly independent, the king to sojourn an equally long part
of the year in each, with no official of either country to accompany
him further than the frontier. In their foreign relations the
countries were to be independent, but to support each other in case of
war. The king was the only tie to bind them together.

There was another Magnus whose candidacy was spoiled by this union. He
was the son of King Birger, already as a child chosen king of Sweden
in succession to his father. Magnus Birgersson, a prisoner at
Stockholm, was beheaded in 1320, to make safe the reign of his more
fortunate cousin. King Magnus was only three years old, and Drotsete
Mattias Kettilmundsson presided over the government during his
minority, the nobles of the state council having great power and
influence. Both in Sweden and Norway the nobility had by this time
attained a supremacy which was oppressive both to the king and the
people, not so much through their privileges as through the liberties