what would possibly exist in the farthest east?

[Rune Son of Bjarne]

Originally Posted by Zigûr

On the contrary, I see the use of chariots by the Easterlings (and elephant cavalry by the Haradrim, incidentally) as evidence that their cultures were primitive, not advanced. Extensive use of chariots was characteristic of pre-Classical cultures like the Egyptians (among many others). The West had steel weapons and mail, advanced architectural techniques, naval technology etc and a generally more early-medieval flavour.

I have always seen the Easterlings' use of chariots as evidence that their development was "held back" by their long history as thralls to the Shadow.

I guess that would be true if the Gondorians had previously been using chariots, and these had become obsolete. However this does not seem to be the case...

It is an interesting question, especially since there can be no doubt that the Kingdoms of Arnor and Gondor was the most technological advanced states in ME at their founding. Arnor disintegrated and Gondor entered something that could be called 'dark ages' where their knowledge waned.

So while other cultures most likely progressed, the Numenorean's regressed.
Would it have been possible for other cultures to overtake them?

[Zigûr]

Originally Posted by Rune Son of Bjarne

I guess that would be true if the Gondorians had previously been using chariots, and these had become obsolete. However this does not seem to be the case...

Does this necessarily follow? The Men of the West certainly used wheeled, horse-drawn vehicles in general. They evidently knew what chariots were by observation even if they didn't use them. I don't see the use of chariots in particular as some kind of 'necessary' step in the technological progress of a society, ie "the Men of the West did not use chariots therefore they were more primitive than the Easterlings."

Frodo himself upon Amon Hen observed the Easterlings as having "swordsmen, spearmen, bowmen upon horses, chariots of chieftains and laden wains" (emphasis mine) which suggests to me that even Easterling chariots were more commonly used for ceremonial purposes and as transportation than as weapons.