Kaigon said:
I think that's a part of an old bug where Astrakhan was able to revolt from some norweigan province...
I heard about the bug, though I couldn't remember the country in question. But I think it had already been fixed in 1.06 which was (and still is) the version I was playing.
From the alliance constellations (astrakhan allied to the turks) and wars (turkish alliance vs. russian/northern allies) it wouldn't have been improbable for such a thing to happen.
In various games i have seen many different armies up to northern russia and scandinavia, e.g. Persia, Turks, Venice, Spain (ok, they are everywhere). But usually they don't succeed and die of attrition and dumbness soon. Winning and keeping the province is not so usual.