The expedition to Finland seems to have…

The expedition to Finland seems to have cost Birger the Swedish crown as an unexpected side effect.

As King Eric died in 1250 and Birger was still absent from Sweden, the rebellious Swedish lords selected Birger's underaged son Valdemar as the new king instead of the powerful jarl himself.

Sources from 1249 onward generally regard Finland as a part of Sweden.

Diocese of Finland is first listed among the Swedish dioceses in 1253.

The first reliable mention in Russian chronicles of Finns being a part of Swedish forces is from 1256.

However, very little is known about the situation in Finland during the following decades.

Reason for this is partly the fact that Finland was now ruled from Turku and most of the documentation remained there.

As the Novgorod forces burned the city in 1318 during the Swedish-Novgorodian Wars, very little remained about what had happened in the previous century.