Charlemagne connection?

There's a common joke that "everybody's a descendant of Charlemagne." Some math...when you go back 1000 years, which is around 300 generations, that's 2^300 = more people that have every lived on this earth. Point is, when you step back that far into genealogy, almost everybody can trace their heritage back to anybody who had a child during that period, and definitely if you are of similar ethnic background. So while not everybody is a descendant of Charlemagne, almost everybody from Western Europe is probably his descendant.