925 - Rollo retired

Rollo
Normandy
Rollo retired, Wiliam Longsword became his successor, he ruled until 942.
Ireland
Gudrød  was defeated by King Muirchertach at Carlingford, where hundreds of Dublin Vikings were taken prisoner and murdered after the battle.
England
Sigtryg gale signed a peace treaty with the successor of king Edward the elder, Athelstan of Mercia and married the sister of Athelstan and flipped over and was baptized.