Erik Birgersson
Erik Birgersson (c. 1250 – 17 December 1275) was a Swedish
duke from the
House of Bjälbo (Folkungaätten) and the third son of
Birger Jarl. While his eldest brother,
Valdemar, was elected King of Sweden and his second brother,
Magnus, was made a duke, Erik initially received no title. Magnus and Erik rebelled against King Valdemar, defeating him at the
Battle of Hova in 1275. After Magnus was elected king, Erik was granted the title of Duke of Småland. However, he died shortly afterward. Erik may have had a genetic disorder known as
Marfan syndrome.
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