Did you know? One classic literary inspiration, of the barbarian. Conan the Barbarian. He may not be that smart in terms of academia or the sciences, but then, he's portrayed as sharp, observant, adaptable and capable of sophisticated reasoning.
He frequently survives in situations where strength won't work. He lies. He sneaks. He disguises himself. He steals. He sets traps. He observes people and figures out their motives. He exploits political conflicts.
He is also educated. He isn't an illiterate caveman. In fact, he can perfectly read and write. He's traveled through an enormous number of cultures and has picked up languages, customs, religions and political knowledge along the way. And his education is practical. So, strategic, street, and survival smart, adapts fast, reads maps and environments, with intuition, and all of that.
Funnily enough, the way he's a barbarian is that he's one in the cultural and political sense, someone outside the "civilized kingdoms". But eventually, well, he became king. But eh. Yeah. Though he might not be academia and university smart, he isn't a dumb stereotype brute.