Nobita's Ancestors (のび太のご先祖さん Nobita no Gosenzo-san) is an episode from the Doraemon 1973 anime.
"My ancestor was a worthy keeper who was able to use the famous lords and was a warrior", says Suneo, who boasts of his ancestors. Envious Nobita asks Dad: "What were our ancestors?", then he replied "they were hunters", so Nobita decided to check with Doraemon in the Time Machine. The ancestor was a coward person and bad hunter. Nobita proposed him to go and fight in the war, but he rejected and Nobita had to impersonate him and made a big success with the tools of the future. At the end, Suneo's ancestor took the credit and Nobita's ancestor remained as how it was.