The East, what we know?

So we have this guy from the East and his name is Shiva. But appart from the distictly japanesesque style weapons what do we know about the place.

Anyone delved deeper into the lore of the east?

If you check out the item description for the Eastern armor set, it reads, "Exquisitely crafted, this armor offers excellent defense, particularly versus slash attacks, which are one of the main threats in the battles in the East." So, at the very least we know katanas are quite common in the East, alluding more to its Japanesque setting.

Good start. +1 for using the correct technical term for things that are like they are in japan aka japanesesque. This is what I mean I've looked at the weapons and rings Shiva sells bu they don't offer a good insight into what the East is.

Anyone else know of any more detailed info such as geography, locations, important persons?

We know that ninja's are common there, as according to the description for the shadow set, "Black cloth clothing worn by spooks from an Eastern land.
Designed so as not to hinder their unique form of martial arts.
While they sacrifice defense for the sake of greater mobility,
they do offer resistance to bleeding and poison among other things, perhaps due to the nature of espionage."

If we put Lordran in the North, all the other countries are west and south (Astora, Carim, Catarina, Thorolund, etc) and the East, well in the east. The items mention that is a land of 'spooks', lol

It seems to be very japanese/asia like. The spooks are probably ninjaesque stealth warriors while the warriors are samurai like soldiers who use katanas.
"Giant curved sword forged using special methods in an Eastern Land."
"This unparalleled weapon cuts like a Katana but is heavier than a
Nata machete. Requires extreme strength, dexterity, and stamina to
wield."
Obviously they are also great smiths.
"Katana forged in an Eastern land. The Katana is drawn from the scabbard at lightning speed, using an Iaijutsu technique."
"Iajutsu allows the wielder to charge forward to swiftly cut down distant foes."
Also Iaijuts is the japanese art of drawing the sword.
Black cloth clothing worn by spooks from an Eastern land.
Designed so as not to hinder their unique form of martial artAnd finally unique martials arts are something most people wouuld attribute to the asian landmass.

All in all it seems like the east is basically the dark souls asia.