Was dual wielding weapons ever a thing in history?

How would that in any way be advantageous? No way that they were used in warfare at all

>warfare
Well, it's rather obvious that dual wielding was more of dueling thing.

Don't know much about this, but I know it was more odpf a decorative thing if ever depicted.

In actuality I'm sure there where moments in war where a guy picked up two swords in battle and started fighting with both.

I know there are techniques in Chinese martial arts that use two swords because I've seen it in demonstrations. However I don't know how new that style of fighting is and i also dont know if its just for show or has ever been used in battle. More likely just duels for sport or show like user said

Yeah
often they'll hold a buckler and a dagger on the other hand in scotland or ireland or whatever.

Yes it was, the so called "Duel of the century" was dual wielding
hroarr.com/wp-content/uploads/downloads/2014/06/Terminiello-Piermarco-Reich-Steven-Fighting-with-two-swords-according-to-Altoni-and-Docciolini-2013.pdf
There where schools that taught fighting with two weapons.

What are the advantages?

It is more deadly and more fun to watch for the spectators.
Seriously, they used shorter swords and a mail glove on the offhand, so this works as a parry device like the later main gauche (see )
It likely takes more to master two blades and hence is a good choice for two experienced fighters like the ones in said duel.

It's not like there's dozens of styles that talks about it in various part of the world...

>the guy to introduce dual wielding katana and wakizashi at the same time.
It was done at least a hundred years before Musashi's birth in TSKSR, and this is just the recorded styles. Besides, there are many many styles that are doing ryoto / nito besides HNIR in the same time period. It's most likely people developing the same stuff at the same time.

Marozzo, DiGrassi and Agrippa at least talk about dual wielding in their treatises. A shield of substantial size is probably always better than another sword in off-hand (especially when projectiles are involved), and is also simpler style of fighting to learn (you don't have to move around a shield as much or use it as actively - this is even more true if you try to actually take advantage of the off-hand sword's offensive capabilities) however such a shield is not very convenient to carry around so a better comparison is sword and buckler, which I wouldn't say is obviously superior to dual wielding. Two swords can be carried rather conveniently in a single scabbard and weight roughly the same as sword & buckler so it strikes me as a feasible choice of weapons for civilian self-defense. Dual wielding also does have some unique advantages:

1. Whatever sword you parry with, you can always strike with the other sword at the same time (in contrast to sword & buckler. Wouldn't be a problem if you always manage to parry with the buckler but that doesn't always happen).
2. Useful for feinting and is more unpredictable
3. The off-hand sword can be used to control the opponents blade better than a buckler
4. Trying to disarm or grapple with a dual-wielder is much more dangerous, if not outright a stupid idea

The points 1-2 apply even when comparing two swords to sword and dagger since the dagger cannot attack at the same distance. 3 applies in the sense that sword can engage with the opponents blade from further away. There are of course also several disadvantages that are well known and often mentioned and I'm not saying the advantages necessarily outweigh the disadvantages in any situation. And while it was definitely a historical thing, it also never was very common. But I think the effectiveness and practicality of this fighting style is slightly underrated by HEMA people in general.

it was common for knights n' sheit to carry two swords but they usually used one with a shield and the other was like a backup, but I have to assume that at some point someone tried to show off and fought with both swords

Yes. Ni ten ichi ryu style kenjutsu, look it up.

If you lost your shield, probably. The massive downside to dual wielding is that parrying attacks is a lot more difficult than it is with a shield, especially when you're not in a 1 on 1 combat situation. Even more so in an actual battle where fatigue is an issue.

Also at least in civilian context, these three things seem to have gone in hand in hand

1. The hilts becoming more protective
2. Blades becoming longer and more narrow
3. The buckler declining in popularity in favor of the dagger

Even though we often think sidesword as something like rapier hilt + arming sword blade, early sideswords could be as simple as arming sword with finger rings. With such not terribly protective hilts it makes sense that they preferred buckler over another sword as otherwise the hands would be rather vulnerable. While there were swords like the "Munich town guard sword", with full rapier hilts AND beefy cut & thrust blades, my impression is that generally speaking a more protective hilt tends to correlate with a longer and narrower blade.

Makes sense because:
1. The heavier hilt brings the point of balance closer to the hand which is good for point control but takes some power away from the cuts.
2. The protective hilt makes it safer to keep the hand extended point towards the enemy, ready for a quick thrust.

As more rapier-like blades became more popular, dagger became a more popular off-hand choice as it was more effective against thrusts and compensated rapier's poor offensive capabilities at a very close range. Using two rapiers wasn't unheard of, and advantages 1-2 apply when comparing it to rapier & dagger, but my guess is that dagger's nimbleness and effectiveness at close range outweigh them clearly, not to mention being quicker to draw when assaulted suddenly.

To be fair, alot of ksr was added throughout its long history, I could have been part of the orignial curriculum, but it might not be.

In any case its pretty unrealistic to think Musashi was the first guy to come up with it.

>Using two rapiers wasn't unheard of, and advantages 1-2 apply when comparing it to rapier & dagger

I meant advantages 1-2 mentioned in

>3. The buckler declining in popularity in favor of the dagger
youtube.com/watch?v=U1Efv-8UsGs
Yet you have non-circular buckler-esque deffensive weapons who apparently survived as companion weapons. Bucklers were popular in England for a longer period as well.

TSKSR is a mid-15th century school, HNIR is an early 17th century school, besides, TSKSR was losing ground at the end of the 16th century.
I think it's a safe bet to say that the ryoto parts of TSKSR are earlier than HNIR's nito.

Anyway, my main beef is that people only ever know about Musashi and HNIR when there are a good dozen of schools that are doing dual-wielding and when the nito kata of this school is the shorter part of the curriculum. Musashi can thanks Yoshikawa for that...

it wasn't used in warfare, but it was sometimes used for dueling

in the early renaissance period when dueling with a rapier you might choose a parrying dagger in your off hand instead of a buckler

From Amdur's writing I take that they were playing with the curriculum through the edo period. Not saying your wrong but before meiji these schools were not set in stone

In fact, the typical weapon we nowadays think of as "rapier" was much more commonly paired with a dagger than a buckler.

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