House of Bjellbo

The House of Bjelbo (Swedish: Bjälboätten), also known as the House of Folkung (Folkungaätten), was an Ostrogothian Swedish family that provided several medieval Swedish bishops, jarls and kings. It also provided three kings of Norway, and one king of Denmark in the 14th century.

The house has been known as the "House of Folkung" since the 17th century, and this name is still the most commonly used in Swedish works of reference. The name "folkung" does appear as early as in 12th century sources, but is then usually not applied to members of the family.

In an effort to avoid confusion with the Folkunge Party some modern historians have argued that "House of Bjälbo" would be a better name because Birger Jarl lived there and it is the family's oldest known manor. Bjälbo is located in Östergötland, outside of Skänninge in the present-day commune of Mjölby. In any case the members of this dynasty never used a name to refer to themselves since family names were not widely adopted in Sweden until the 16th century, thus neither name is more "correct" for the dynasty, apart from the potential for confusion.

The House of Bjelbo produced most of the jarls in Sweden in the 11th, 12th and 13th centuries until the title was abolished in 1266. Different branches of the family were often rivals for the office of jarl. Most of the kings during that time were also from Östergötland.

Around 1100, Folke the Fat became the first known Bjelbo jarl, and probably the first jarl of all Sweden, under king Inge I of Sweden. He was married to a daughter of king Canute IV of Denmark. According to legends, he was the first of his family so elevated. Nothing is known of any of Folke's collateral relatives, though it is well-established that several of his sons' descendants were important lords.

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