911 Duchy of Normandy established

France
The duchy of Normandy was established, Chartres was attacked by vikings from the Seine area. The citizens of Chartres fought bravely and received help from Paris. After a devastating defeat in front of the city gates the vikings had to cancel the siege and retreat. Charles the simple met with the viking leader Rollo(Rolfr) in St. Clair-sur-Epte. Rollo was the son of a Danish chieftain, he was driven out of Denmark according to the Norman medieval historian Dudo. But The Old Norse Kings’ Sagas, an important part of Norwegian and Icelandic history, claim that Rollo and Ganger-Hrólf(Rolf the walker, got the nickname, because he was to big to sit on a Viking horse) are one and the same person.Answers in 2016 when Norwegian and French authorities present the results from the analysis.
Rollo, Duke of Normandy
Charles the simple completely legalized the viking control of Normandy, by making Rollo a French duke and gave him the area as a duchy. The Franks definition of the vikings: Norman, later became the new name for the duchy. Carolingian documents informed us that the Scandinavian raiders received 19.5 Tons silver and 300 kg gold
Statue of Rollo
England:
The Wessex kings brave sister Aethelflaed of Mercia led an army against the vikings and defeated them at Wednesfield, Mercia. And after her victory she and her brother the king started to rebuild castles and build new castles at strategic places now they could be a danger to the Danelaw area.

Aethelflaed, Lady of Mercia

The rulers of Northumbria: Ragnvald and Sigtryg Gale (Both of the Norwegian royal Dublin dynasty) was now alerted and worried. 

Greece

Prince Oleg of the Rus and his Slav allies made a treaty with Byzantine, Leo the wise recognized the fighting qualities of the Rus and began hiring them as mercenaries known as the Varangian guard.

Ireland

Drogheda was established as a Viking settlement on the River Boyne.