Germania  

, ゲルマン

The character you are referring to in the anime adaptation is known as "Germania," who was a friend and guardian of Grandpa Rome during his time in the Holy Roman Empire. He had striking green eyes and long blonde hair that he tied off to one side of his head in a small braid. In later adaptations, his braid was removed and his eyes were changed to blue. Germania bore an uncanny resemblance to Germany, which led many viewers to speculate about his true identity. Despite their initial friendship, the two eventually became enemies, with Germania delivering the final blow to a weakened Grandpa Rome. Shortly after killing him, Germania also passed away. Not much is known about Germania's personality, but he was portrayed as an intimidating and brutal warrior who preferred discussing politics over hearing Grandpa Rome's rants about pretty girls. While it is possible that he may represent the region of Germany, Germania has only been confirmed to symbolize the Germanic Tribes in the anime adaptation.