I'm curious when the earliest mention of the game is and if it was indeed popular in Russia?

Malcolm X in his autobiography reports playing Russian Roulette with a six shouter with two rounds. He puts the gun to his head and pulls the trigger four times. He claims that after doing this, all his friends "respected" him because he was so crazy. That combined with his lack of care for his life before converting to Islam is why he did this.

I'm not sure if I fully believe the story, but that's what he claims.