Erik I of Sweden did his crusader service among the Finns during the 12th century, marking the start of Sweden’s 700-year annexation of Finland and Erik’s climb to the status of his country’s patron saint.
But aggrandizement was all too easily reversed, as occurred in Denmark on Valdemar II’s exit. “The crown fell off the head of the Danes,” a chronicle wailed, “and they became the laughing stock for all their neighbors through civil wars and mutual destruction.”
Like the Church, German and Dutch Hansa traders recognized the chaotic absence of government as an excellent opportunity. Scandinavia had an abundance of fish but a shortage of grain. By tying up the markets in both commodities, and the shipping in between, the Hansa had a goose of pure gold, and it gave them a network of strategic ports and market towns across the continent.
But if Scandinavia was sapped by an extortionate exchange rate between fish and grain, it was then poleaxed by the Black Death in 1349. With the population of Norway for example, cut by more than half, economics reverted to the Stone Age.
One interlude in the slow reconstruction process was the arrival of shoals of herring so dense that fish could be caught with bare hands. Fishing vessels raced from all over Europe until some 40,000 were crammed into the Sound, temporarily loosening the Hansa’s grip on the market.
The 14th-century king Valdemar IV of Denmark launched a snap invasion of the Hansa’s base at Visby in Gotland and, flushed with success, assumed the title of “King of the Goths”. The Hansa were not amused. Throwing the resources of their 77 towns and cities into a military alliance with Swedes, they bounced Valdsemar off his Danish throne and invited applications.
Margrethe, the young wife of King Håkon VI of Norway, proposed their son Oluf. He was five years old.