As I've been doing research on pre gunpowder weapons, the most commonly used weapons were clearly the spear and the halberd/poleaxe- both long reaching arms. Does that make a sword useless? Absolutely not, was the spear or poleaxe ever issued to naval forces that might have had to fight off a boarding party? No, it was a sword because the reach of a polearm was not needed, nor practical.
That said, I don't see any instances where I would likely use one, even if it were after a nuclear apocalypse and ammo was gone, I'd just as soon use a flintlock or a percussion gun.
Then again, in close quarters decapitating someone with a sword is pretty effective, but I could probably do that with a sharp bladed axe and the axe would be more useful with its wood chopping abilities.