>>314870590And Vikings were historically untrained raiders who liked to do their raiding naked because they knew they faced zero real threat. If we're talking that historical fiction described in OP's image, sure, give it to the "Viking," but historically, anybody who didn't immediately panic at the sight of over 6 feet and 200 pounds of naked, muscled masterrace running at you with an axe in one hand and his own beard-braid in the other had a decent shot of taking at least one Viking out if he could find a pitchfork.
Since Samurai were disciplined, trained, and armed, they'd probably win, even with the height disparity.