[citation needed] According to tradition preserved in Vadstena Abbey, Bishop Hemmingus of Åbo would have prevented the appointment of Bengt as the Duke of Finland.
However, Bengt's sigil from 1355 includes the phrase Secretum Benedicti ducis Osterlandiarum et Hallandi, indicating that the possible resistance had been overcome by that time.
[citation needed] In 1357, Bengt was exiled and Scania as well as several other Swedish and Finnish provinces were given to the young king Erik who ruled the kingdom together with his father.
Duke Bengt's elder brother Knut Algotsson [sv] was exiled to Norway with his wife Märta Ulfsdotter, a daughter of St. Bridget of Sweden.
[citation needed] According to tradition Bengt Algotsson was besieged in Rönneholm Castle in Scania and killed by his brother-in-law Karl Ulfsson and Magnus Nilsson Röde.