This successful invasion of England was lead by William the Conqueror. This introduced European style governance to England as well as the influence of a French language, which was spoken in court for 200 years after.
Norman Invasion
This Empire declared itself to be the descendants of Rome even though most of its kings and lands were in Germany.
The Holy Roman Empire
This was a series of conflicts over 400 years between Christian invaders attempting to capture the Holy Land in the Middle East.
The Crusades