After reading many a fic and looking at a map of Japan itself, I couldn't help but wonder what constitutes the Western Lands, the Eastern Lands, the Northern or the Southern Lands for that matter? I mean, Japan is made up of many islands varying in size and if you look at it, Hokkaido and maybe the northernmost part of Honshu would be considered the Northern Lands. The Western Lands and Eastern Lands would be a bit tricky to divide. Shikoku would be part of the Western Lands and maybe Kyushu with the Ryukyu Islands extending to Okinawa would probably be included as well, making it the largest territory. The rest of Honshu would be considered the Eastern Lands. But the Southern Lands would geographically only consist of the tinier islands south of the mainland. I don't know. What does anyone else think? Here's a link to a map of Japan for reference.

Map of Japan

Hm...looking at the map, I'd agree that Hokkaido would be the Northern Lands.
I can also see the islands south of Shikoku to be the Southern Lands.
As for the Western and Eastern lands, I would think anything east of the Shinano River would be Eastern territory, and the west of it would be the Western Lands(including the island of Shikoku).

Hm....what i'm thinking is that, 500 years ago, the land was probably different, the island known as japan was probably in a more....solid shape, i'd wager. But, going off that map...

North: red
South: yellow
East: blue
West: green

I agree with Kitten. The Shinano River would serve as a natural border between the east and west. Although Shikoku could easily be part of the southern lands, too.

But given the era, I imagine that official territory borders could change quite often, depending on the battles fought over different areas. And I have read a number of stories where Sesshoumaru is battling other lords for control of their lands.

At the battle of Sekigahara in 1600 where Tokugawa won the shogunate by beating the other regents of Hideyoshi's son, the Western forces were those from Kyushu and the south part of Honshu. Tokugawa's allies were considered the Eastern forces were centered around Edo. The western lands should be those circled in yellow on the map for Sengoku Jidai Japan. This is why many of early Inuyasha fanfic writers placed the Westrn Shiro in Kyushu.

Well, the only problem with that I see is Kagome being from Tokyo. Wouldn't that make the well in the feudal era still in that place? It only mentioned traveling through time not space after all. Though I guess it's all fantasy and people could say I'm thinking to hard.

Could be that whoever the lord of the eastern lands was they didn't have very many...Sesshy is pretty B.A. after all..