Short answers, pulled from the story.
Eric the Victorious was a Swedish monarch who began ruling around 970 and is regarded as the first Swedish king in a consecutive line attested by independent sources. He earned his epithet, meaning Victorious or blessed with victory, after defeating an invasion force at the Battle of Fýrisvellir near Uppsala.
According to the tale Styrbjarnar þáttr Svíakappa, Eric defeated his nephew Styrbjörn the Strong at Fýrisvellir after sacrificing to the god Odin and promising to give himself to Odin within ten years if granted victory. Two skaldic verses by Thorvaldr Hjaltason describe Eric's outnumbered forces capturing the invading Vikings, with only those who fled surviving.
Adam of Bremen and Saxo Grammaticus both report that Eric became king of Denmark after defeating King Swein Forkbeard, with Saxo stating Eric ruled Denmark for seven years. The historian Peter Sawyer disputes the scale of this account, calling Adam's version a gross distortion of what actually happened.
Eric agreed to baptism while staying in Denmark, which would make him the first Swedish king to convert according to Adam of Bremen. He is said to have later forgotten the Christian faith and reverted to the religion of his ancestors.
Sagas name four possible wives for Eric: Sigrid, Świętosława, Gunhild, and Aud, though two or three of these may have been the same woman under different names. His four known children were Olof Skötkonung, Emund, Holmfrid, and an unnamed daughter who married a man named Åke.
Adam of Bremen's account dates Eric's death to between 992 and 995, while Snorri Sturlasson states he died at Uppsala. The historian Peter Sawyer argues instead that Svein Forkbeard defeated Eric in 992 or 993 and that Eric died during or soon after that war.