The French

In 1066 William the Conqueror of France defeated King Harold II of England at the Battle of Hastings and became King of England.  William was French and Harold was English. 

William was a direct descendent of a  Viking, Robert (Rollo) Ragnvaldsson,  who was  Duke of Normandy 1st.  Rollo was born in Norway in 870.

Harold, the last Anglo Saxon King, was otherwise known as Harold Goodwineson, and was descended from the Danish Vikings. 

Some might say, therefore, that the 1066 dust-up was no more than a Scandinavian altercation between two Vikings.