Conan is the prototypical D&D barbarian. Conan went into blood rages ALL THE TIME. He also hated wizards and civilization. Hence, all the original Barbarian traits and tropes.
As an aside: making Native American culture, which still exists today, the definition of "barbarian" is an iffy take.
As an aside: making Native American culture, which still exists today, the definition of "barbarian" is an iffy take.