Björn III 'the Old' Eriksson King of Uppsala
- Born: Abt 865, Uppsala, Uppsala, Sweden
- Marriage: Mrs. Bjorn Eriksson
- Died: 956 about age 91
Björn (ruled 882-932) was the father of Olof (II) Björnsson and Eric the Victorious, and he was the grand-father of Styrbjörn the Strong, according to the Hervarar saga and Harald Fairhair's saga. The latter saga relates that he ruled for 50 years. According to the two sagas, he was the son of an Erik who fought Harald Fairhair and who succeeded the brothers Björn at Hauge and Anund Uppsale. Erik Anundsson is the only Erik who fits.
In Olaf the Holy's saga, Snorri Sturluson quotes Thorgny Lawspeaker on king Björn:
My father, again, was a long time with King Bjorn, and was well acquainted with his ways and manners. In Bjorn's lifetime his kingdom stood in great power, and no kind of want was felt, and he was gay and sociable with his friends.
When Björn died Olof and Eric were elected to be co-rulers of Sweden. Eric would however disinherit his nephew Styrbjörn.
Adam of Bremen, however, only gives Emund Eriksson as the predecessor of Eric the Victorious. Since the Swedes seem to have had a system of co-rulership (Diarchy), it is probable that Emund Eriksson was a co-ruler of Björn's.
Björn married Mrs. Bjorn Eriksson. (Mrs. Bjorn Eriksson was born about 872 in Sweden.)