Answer:
King of the Franks
Step-by-step explanation:
A) Charlemagne also, known as Karl and Charles the Great, was a medieval emperor who ruled much of Western Europe from 768 to 814. In 771, Charlemagne became king of the Franks, a Germanic tribe in-present day, Belgium, France, Luxembourg, the Netherlands and western Germany.
B) He is known for his military successes which united most of Western Europe