Writing Your Protagonist: The Fighting-Man

There's something about a classic fighting-man as the protagonist that never fails to deliver. From Burroughs' John Carter to Howard's Conan and beyond to the present day, you cannot move two steps in a bookstore without finding someone using a fighting-man as a protagonist in genre fiction.
This isn't hard to figure out. Look at what real fighting-men. To succeed as a fighting-man, you have to have the very qualities of character that define a heroic protagonist: a desire for action, skill at combat, and a combination of excellence and determination to see through to the end. From the earliest heroic epics to today's pulp fiction, unless it's specified otherwise you can count on that protagonist being a clean-limbed, strong-armed, action-ready fighting-man.
As we've seen over the generations, you can easily and readily adapt this iconic figure for every genre of adventure and intrigue known to Mankind, so it is no surprise that the fighting-man is one of the go-to protagonists in fiction. If you're new to writing your own, master this archetype first
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You don't have to get into how any special powers work with a fighting-man protagonist, and you can do as the masters did by having your protagonist be an outsider so that the reader learns about the world at the same pace as the protagonist. You can do your research easily online, reading up on historical periods, styles, events, etc. that inform your protagonist's demeanor (and thus how you characterize him).
Barbarian fighting in Rome's gladitorial games? Fighting-man. Knight-Templar fighting off Assassins? Fighting-man. Navel officers chasing pirates in the Caribbean? Fighting-men all around. Zulu warlord chosen by the gods to fight for them? Yep, a fighting-man. Two-fisted brawlers taking on crime syndicates? Post-apocalyptic swordsman walking the earth dispensing justice? No actual formal military experience required; they're fighting men, not soldiers as such (though that is common). Your MMA fighter is as much of a fighting-man as the Winged Hussars.
By giving those examples, I also showed the archetype's versatility (and therefore its resilience). As you find your footing with your writing, don't be surprised to catch yourself not even thinking of the fighting-man as a protagonist archetype to itself; much like how the classes of Dungeons & Dragons started with Fighting-Men, so does heroic literature in general, and all other archetypes get their meaning by contrast with this one. Go on, ride this bronco good and hard, break it in. Once you've got a full and complete comprehension of the fighting-men, every other protagonist becomes much easier to master in turn.