"They were both", exept the fact that Babel was Jewish in origin and also wrote in Russian.
The "gogol" in Ukranian means "a drake" AFAIK.
But since Gogol wrote in Russian and NOT in Ukranian (besides, he lived in S.-Petersburg for some time and communicated with Pushkin), he is Russian writer. And one of the best. I think he is the best in prose.