Probably not directly, but indirectly you definitely are. The assertion of Charlemagne being the Father of all Europeans is metaphorical, but also autosomal. The study looks at both matrilineal and patrilineal decent. It's the same theory as "Six degrees of separation". When you think of the crazy spider web of relativeness it becomes clear. It's difficult to wrap your mind around.
Example: A male I1 marries a female U5a, they have four kids all I1 and U5a autosomal. The daughters marry a R1b men, and a J2 man. The Sons marry H3 woman, and T1a woman. The grand kids who are I1,R1b, and J2 yDNA and U5a, H3, and T1a all have a common ancestor of the grandfather who was I1. Bring in human mobility and 50 generations and you can see how we are all related from a dominate male figure like Charlemagne. His decendents married and had children in Slavic, British Isles, and Scandinavian countries. There are a lot of bastard children out there. It wasn't unheard of to sleep with your vassals bride. The French call it "Droit du seigneur" right of the lord.