If you really want to do a side by side comparison between the longsword and the katana, well, there’s not much to compare. 

The longsword is longer, obviously. They weigh about the same, but weight doesn’t matter nearly as much as weight distribution. The katana is shorter, so it’ll be a little bit handier in the cut, but it’ll suffer in the stab. Call it a draw.

You want to compare the quality of the construction? Fine. Katanas, especially in later years, tended to be regarded as much as works of art as they were weapons, and thus, employed a high degree of craftsmanship in their construction. While fine examples of the longsword surely existed, most would have been fairly workmanlike in their fit and finish. The katana wins the beauty pageant, but they’re both fully functional. 

The quality of the steel? Tamahagane wasn’t (and still isn’t, it’s just fantastically overhyped) good steel. But you know what? Neither was the overwhelming majority of shit coming out of Europe during the longsword’s heyday. Granted, the ore found in Europe was often of a higher quality than the iron sands of Japan, and that combined with the through-hardening of European swords gave them the ability to flex without taking a bend. But, the katana wasn’t designed to be flexible, and its rigidity helps it in the cut. Will the katana take a bend if you try to use it wrong? Sure. Does the longsword lose cutting power due to its flexibility? Yup. Call this one a draw, too. 

It’s a slightly different story if you want to use modern steel, mind you. Differential hardening with modern monosteel can still give you that razor edge on the katana without all those pesky impurities. And of course, a modern longsword made of spring steel will quite happily bend at absurd angles. Both are superior to traditionally made tamahagane blades. All we can really conclude is that the past sucks and we should stop trying to pretend otherwise. 

But wait! You cry. You just said the katana is better in the cut. Surely that’s a point in its favor. Well, yeah. But then again, it’s better in the cut than all but like 3 types of saber. It’s designed to cut. That’s what it does. Sure, it’s a point to the katana, but it’s not nearly so impressive when Michael Jordan wins the pickup basketball game, is it?

The same goes for the longsword and stabbing. Rapiers are a hell of a lot of fun and all, but trust me, you really miss that extra grip length in the bind. Smallswords? Spadroons? Eh, sure, they’ll poke holes I guess. But they don’t really do anything the longsword doesn’t in that regard, they’re just more convenient to lug around. Point for the longsword.

Oh, speaking of longsword points and stabbing, they do better against armor. The katana isn’t meant to go banging around off of steel plate, but whatever. Point for the longsword. 

Are we done? Can we stop pretending there’s any merit to this discussion?

Bah. Fine. Fuck you, knights versus samurai. We’re getting a bit far afield, but you keep moving those goal posts if it makes you feel better. 

One was a warrior born from a noble class that devoted his life to learning how to fight in service of his lord. The other was a warrior born from a noble class that devoted his life to learning how to fight in service of his lord. One learned an intricate system of martial arts developed over the course of centuries in the heat of battle, while the other learned an intricate system of martial arts developed over the course of centuries in the heat of battle. 

There is no practical efficacy or skill difference between kenjutsu or iaido and their HEMA equivalents. They were designed for different weapons, so the movesets vary somewhat, but they’re a lot more similar than people give them credit for. Turns out, there’s only so many biomechanically sound ways to use a two handed sword efficiently. There’s a shit ton of overlap, is what I’m saying. 

And I swear to god, if the words honor, chivalry, or bushido come out of your mouth next, I’m gonna reach through this screen and strangle you. Make like Elsa and let it go. 

It’s like I’ve said all along: this comparison is pointless. We could go on for hours, coming up with hypothetical situations in which one sword might win over the other, but it’s just as easy to come up with one in the other direction. It’s still a tie game. It always has been, and it always will be. 

Both swords excel in the roles they were designed for, and they’ll suffer in comparison when pressed into service outside of their intended use cases. The only question that really matters when choosing between the two is what you need the sword to be able to do. 

In fiction, where things like edge geometry and crystalline structure don’t matter, the question is even simpler: which one do you think is cooler?

I’ll admit, I’m a little biased in the longsword’s favor in this department, purely because I’m a little more comfortable sparring with it. The sort of cuts the katana favors can be really scary to execute in practice when you’re not trying to hurt the other guy, especially when you’re built like a shaved sasquatch. With a longsword, it’s easier for me to go for the bind and ragdoll the other guy, since I don’t have to worry about breaking collarbones through practice armor that way. 

If you really want the full experience, have a character who focuses on trying to stab, rather than swinging the blade around like Conan the Barbarian. Make the combat a chess game, rather than a slasher flick. Really get inside the heads of your characters as they fight and show the audience that they have to outsmart their opponent to win. 

But hey, if you prefer the katana, go nuts. Let your weeb flag fly. It’s still a pretty great blade. If you want, you can even use realism to add an element of tension. Have the MC be mindful of the risk of bending the blade, and have them focus on getting the perfect edge alignment for the perfect cut. Off the top of my head, that seems like a pretty good way to demonstrate some sort of emotional strife, and knowing that they have to be careful in battle builds suspense and opens up all sorts of hitherto unsuspected tactics. 

Or just have them slice through boulders or pretend the longsword weighs 40 pounds or whatever, I really and truly don’t give a shit. At the end of the day, it’s your duck to fuck. I’m just here to hold the wings.