Normally when I think of a Samurai I just think of your typical generic samurai with his basic bitch armor (I actually have no idea what kind of armor they wore) that's whatever color, a kabuto that may or may not have a face piece (a menpo right?), and then whatever weapon they may be carrying.
I learned from here that samurai basically bring whatever weapon they like to the battle field with them, which makes sense to me.
Although, I'm not too sure if this is exactly the same when it comes to their armor.
So I have a couple of questions that stem from this:
Was there any sort of "standardization" when it came to a samurai's armor? If I were a samurai that fought for the Oda clan, what would I HAVE to wear besides the clan's sashimono (I'm thinking more like a specific color scheme on the armor maybe, or some sort of identifying piece other than a sashimono to make the army look more homogenous).
Would a samurai in any case ever not wear his Kabuto? And if so, how common was it? Like maybe wear a headband or Jingasa instead?
Probably a stupid question, but did EVERYBODY have a Sashimono?
How did samurai armor vary, and did every samurai just use one type, or did they all use a different type?
Also, a very unrelated question I have since I don't want to make another post for it: Were Warrior Monks (Sohei) ever actually enlisted into a clan's military?
I know the monks of Honganji had a little alliance with the Asakura and Azai, but I wonder if they were actually employed into these armies or not.
As far as I know there were general styles of armour of corresponding periods, but besides a couple specific famous units that had their armours painted specific colours, there was probably little formal clan-wide standardization. Like their own weapons, samurai more-or-less chose their own armour. Of course as they were responsible of outfitting ashigaru and lower-class samurai, we might expect to see the same style of armours in a team or section or even a company as they ordered their armours from the same blacksmith.
What, if anything, you wore on your back kind of depends on your position. Ashigaru are unlikely to be wearing anything. Their team commander samurai might have a sashimono, or might have a flag carrier beside him, or both. The 兵要緑 says all samurai of the mounted team should have a sashimono, but screens like this and this depicts things a bit unevenly on whether mounted groups all had sashimono. The 兵要緑 says all mounted should wear the same style of sashimono, though you can see in the screen that some wear their own clan's instead of their lord's clan. The 兵要緑 is silence on what samurai on foot wear on their back, if anything, and again, screens display differently, some yes some no, seemingly depends on their position in the unit. You might also notice that in one of the screens, the lord's bodyguards are wearing horo instead of sashimono.
Unlikely in battle. Jingasa was worn by lower class troops. A Kabuto both offered more protection, was more expensive and a status symbol, and likely had your own family crest on it so you kind of want to wear it to be identified.
No. See above. This is one of the things games/dramas/movies get wrong.
There were definitely different designs for different armour pieces. The most visibly different is the kabuto, with a lot of outrageous crest designs for identification purposes of the commanders, and cuirass (off the top of my head: multi-layered more traditional, or single-piece flat, single-piece but shaped like multi-layered to look more traditional, muscle cuirass, and European-design with a middle ridge).
Individual monks who became warriors or samurai who became monks aside, sohei groups were independent political/military forces, and strong clans all over Japan made a point of limiting or disbanding them (often by force, the Oda wasn't the only one).
Honganji was busy fighting its own battle in the Kii Peninsula against Nobunaga, so no I don't think its forces were ever sent north to join the Azai and Asakura, at least not in significant numbers that I've ever heard of. However I am not ruling out small groups of ikkō ikki answering Kennyo's call to oppose Nobunaga by joining Azai/Asakura forces.
