All of those languages and more are linked in the sidebar, what would you prefer to see?

You know, I never knew that that sidebar was a link to the same entry in different languages - thanks! Still, it makes me wonder if there is still a way to open up more content in other languages, so that those who contribute more in-depth can somehow have that content be shared on other language pages more transparently. But, I never studied library science and I'm sure finer minds than mine have considered this problem.

The tricky thing is that any text content has to have translation. You might be able to get away with not translating maps, since place names tend to be more stable (or at least generally pretty easy to work out) across different languages. For example, "Pologne-Lituanie" is going to be within the capability of most English speakers to work out, even if they've never heard of "Poland-Lithuania".

It is possible to link images and other things via Wikimedia, and my understanding is that Wikipedia does push for people to do this.

It links to articles in over 80 languages. So on one hand it does a really good job at cross linking. On the other hand, missing out on linking to the languages you mention seems like a huge error.

It does link to all those languages. I think what the grandparent was referring to is that there's no way to indicate that an article in another language might be interesting in some way.

Such as, for Carnival, being written in a language spoken by a people who celebrate it, or for Alexander the Great, highlighting the languages spoken in territories he conquered.

It's an interesting proposal, but I get a headache just thinking about the politics of implementing it.