991 - Vikings defeated and killed ealdorman Byrhnoth

Byrhnoth, Earl of Essex slain in the Battle of Maldon

The site of the Battle of Maldon showing the extensive areas of salt flats and marsh which restricted where combat could take place

England
10th August: Olaf Tryggvason,was a warrior king who could use his sword with the left and right hand completely smooth, Olaf Tryggvason could also juggle with three swords at once.He defeated the Wessex English at the Battle of Maldon. Vikings defeated and killed ealdorman Byrhnoth, the earl of Essex an old English battle poem tells the tale. Aethelred payed 10000 pound silver to Olaf Tryggvason.

Denmark
Sweyn Forkbeard regained the Danish throne.
Orkney
Sigurd the stout Hlodvirson became the earl of Orkney.