The House of Bjelbo, 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.

Östergötland is one of the traditional provinces of Sweden in the south of Sweden. It borders Småland, Västergötland, Närke, Södermanland and the Baltic Sea. In older English literature, the Latinized version Ostrogothia is also used. The corresponding administrative county, Östergötland County, covers the entire province and parts of neighbouring provinces.