"16th century onwards" and "civilian situation"
Gunpowder gets invented, muskets become widespread, heavy armor and shields become mostly obsolete, agility is now more important, and that's why rapiers become viable, and that's why you are using a dagger as an offhand instead of a shield which is harder to carry anyway.
I'm pretty sure you're not going to see an armored knight wielding a rapier and a dagger, nor is the rapier going to be very effective against plate armor.
one of these days (
ha. haha. hahahahahahahaaaaaaahfuck. when I'm not running around like a demented maniac trying to produce a small armoury's worth of weaponry for my job), I need to write a long essay on the subject of exactly why you don't get Vikings with rapiers. its a really interesting subject, all about the intersection of many different conditions - everything from the infrastructure delivering metal to cities, to the social laws governing them, all make significant impact on what was used, as much as the simple condition of what armour was like - armour is almost as much a product of those criteria too. Its fascinating, but very intricate.
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Regarding dual wielding as a subject, despite my history fascism inclinations, I'm personally OK with the idea, as long as a number of general conventions are followed - namely.
1: both weapons are single-handed in normal use.
you don't use two great swords of war, or two pole-arms. its just not practical in any way with more than two single-handed longswords - its just too difficult.
Ideally, it should penalise anything that's not "well balanced" - to fight effectively with them, you need them to be using agile weapons.
2: the second weapon is shorter than the primary weapon, unless the primary weapon is also short, in which case, both can be equal.
almost every fighting style with two weapons - japanese katana and wakazachi, genoese rapier and main gauche, indian pata and katar, uses a larger main weapon, and a smaller weapon that's lighter to defend with, that can be occasionally employed to make attacks when the opponent is bound up.
There's a few very unusual exceptions to that - the "case of rapier" is referenced in both Camillo Agrippa
(Yes, for those who've watched Princess Bride, THAT Agrippa. As in Agrippa, which helps if the opponent is using Thiabault, since the opponent may use Capo Fero, against Bonetti's defence... Those are all real fencing masters. Though sadly, the film duel, choreographed by the late Bob Anderson, doesnt use any of the real techniques... But I digress) and in Heredia. but that's a very specialised technique for the duel, in very strictly controlled contexts. its also rather static, and visually uninteresting as a fighting style.
3: the two weapons aren't used to attack at the same time - its one of the true historical fighting styles where there is a degree of tempo - an attack is defended against, the weapon is used to bind, the other weapon strikes the bound opponent. you never leapt in swinging both weapons to hit at once - that's a suicidal move.
As long as those situations are followed - not because a historical fighting school used them, but because they're determined by the reality of physics, human ability and co-ordination - then I'm perfectly happy with two weapon use. Two daggers? Yes. Axe and cleaver? why not? Falchion and rondel dagger, one cutting, one stabbing weapon? I'd like to see it.
its when it becomes two huge weapons being spun around and the attack leaping in to hit with both, that two weapons becomes an absurdity.
