Charlemagne was king of the Franks in the 700's. He devoted his time to conquering lands in Europe. His empire soon grew to almost match the size of the Roman Empire in it's height, and eventually included part of the Roman empire that existed in his time. Because of that, he was crowned Emperor of the Romans by Pope Leo III.
Charlemagne's empire was doomed to fall, due to weak rulers in the future, but while it existed, it consisted of all of modern France, along with parts of modern Germany, Austria, Spain, and Italy. Furthermore, Charlemagne's people, the Franks, were a Germanic tribe, but eventually became the people modernly known as the French. One of the important rivers for the French, was also important for the Franks. The River Seine provided them with a steady water supply, and more. As I said earlier, soon after Charlemagne's death, less strong rulers caused his empire to crumble both externally, from attack, and internally, from mismanagement.
Charlemagne also sponsored many schools when he was alive, especially in his capitol of Aachen. His schools were most likely run by monks, so Charlemagne indirectly also help