What did Charlemagne contribute in our history?

Answer

He is credited with halting the Arab advance into Europe. Were it not for that, Europe would have been made of Muslim countries as well as Christian ones. Portugal and Spain may never have existed, meaning the exploration of the New World may not have started for centuries after it did. I guess you could say he contributed everything.

Answer

Charlemagne was the greatest mover behind the Carolingian Renaissance, which was very important in shaping the subsequent history of Europe, because it changed the standards of education built schools, and codified the laws. He protected the pope when he was in peril. He built a great empire that was the forerunner of both France and the Holy Roman Empire. Of all of the monarchs of the Middle Ages, he may have been the one who most influenced modern society.