Regarding Shogun 2 General's bodyguard unit.

[Sp4]

Why do they have huge baloons on their backs?

I assume it has something to do with their standing in society and all but surely they must have some practical use as well? I can't get myself to think people would drag these things around in battle xD

Here's an image (not taken by me)

[Kagemusha]

That balloon is a horo: http://en.wikipedia.org/wiki/Horo_%28cloak%29

[Sp4]

How do they protect from arrows?

[Kagemusha]

How do they protect from arrows?

It has been very controversial discussion if they actually did protect at all.We are more or less left guessing if they actually did give protection. I have seen one test from an horse archery specialist testing a Horo on horse back and arrows were stuck on it.Of course silk is tough fiber so it would have slowed down arrows shot from behind and the Horo cloak might have made it harder to aim by abstracting the outlines of a mounted samurai.Still there is nothing conclusive about the benefits of Horo, so it is bit of mystery.

[Sp4]

Yeah, I was thinking it makes aiming harder, but that is about it. I can't see a silk bag filled with air stop arrows, especially if worn on the back oO

[Papewaio]

Enough layers and it would stop arrows.

Silk is natures Kevlar, so give enough layers and a curved surface and you can either stop or deflect arrows or bullets.

[Sp4]

Yeah but they wear it on their backs... It might help them when running away from archers. Other than that, the only thing I can see this does is make it harder for the archer to aim. On the other hand, it hardly mattered if they could make out the individual man because they never aimed for the individual man but rather the entire unit.

I'm thinking it is just a ways for soldiers/warriors to identify their leaders, which probably makes leading an army easier.

[Watchman]

That'd only make sense if it was The Boss himself wearing the thing, and doesn't really compute already because it doesn't make him any easier to pick out of a crowd (unlike, say, particularly tall and distinctive helmet decorations which were pretty popular among commanders...) Plus the things were AFAIK specifically worn by their *bodyguard* units, the hatamoto ("under the banners", ie. the retainers immediately surrounding the lord in battle), and as such smack more of a badge of rank and a sign of ultra-élite status.

The "arrow curtain" effect was arguably mostly a fortunate coincidence, especially as it's only fully effective when moving at high speeds makes the thing fully billow out and at this level the warriors would in any case be armoured to the highest possible period standards anyway. (A more generally effective means of extra protection from arrows and other sharp stuff is to wear a layer of strong silk *under* your armour.)

As far as tactics go, do recall that Japanese lancers fought according to the general Eurasian model of fluid repeated attacks, not the particular European manner of a single "do or die" linear assault - so in that regard extra arrow protection on the back makes sense enough. 'Course, you'd then expect the practice, in one form or another, to be quite widespread among the rank-and-file cavalry who did most of the actual fighting, since obviously the lords' most trusted and elite personal guards were only thrown into the fray when there was a real reason to. AFAIK it wasn't, suggesting whatever extra protection it gave wasn't really worth the trouble (given that, like cloaks, such garb would rather seem to present enemies in general and swarming infantrymen in particular an only too obvious handhold to grab in an effort to haul the horseman from the saddle - plus it would rather seem to fail to protect the rump of the horse itself from the selfsame arrows).

[Kagemusha]

Yeah but they wear it on their backs... It might help them when running away from archers. Other than that, the only thing I can see this does is make it harder for the archer to aim. On the other hand, it hardly mattered if they could make out the individual man because they never aimed for the individual man but rather the entire unit.

I'm thinking it is just a ways for soldiers/warriors to identify their leaders, which probably makes leading an army easier.

Like you said. As Horo was mostly used by the bodyguards and messengers of Daimyo.Maybe indeed the main use of it was ease of indentification. Though for example the Tsukai Ban personal messengers of Takeda Shingen and Tokugawa Ieyasu did not use horo, but sashimono, while ones of Oda Nobunaga and Toytomi Hideyoshi did. To me this is one of the pecularities of samurai heraldry which we might never get an simple answer.