Russia is a country that straddles both the East and West, and is culturally very diverse.
Why and how did so much of Russian literature become part of the Western Canon?
To put it another way, why are Tolstoy, Chekhov and Dostoyevsky considered part of Western literary culture or part of the Western canon?
Is it because of the themes of Russian literature or because of some historical event or just because of geography or something else?
For context the following definitions apply:
Russian Literature = refers to the literature of Russia and its émigrés and to Russian-language literature.
Western Culture / Canon = refers to the book by Harold Bloom entitled "The Western Canon: The Books and School of the Ages". Please review that book if further clarification is needed.
culture = the arts and other manifestations of human intellectual achievement regarded collectively.
West / East = refers to west of the Ural Mountains / east of the Ural Mountains until you hit the International Date Line.