Leo Tolstoy is considered one of the greatest writers, and is most famous for writing War And Piece and Anna Karenina. He was also a moral philosopher and a Christian Anarchist excommunicated by the Russian Orthodox Church. The Kingdom of God is Within You and A Confession are a couple of his more notable writings on Moral Philosophy.
Tolstoy - The Moral Philosopher
Tolstoy explored Christianity, Science, Greek and Eastern philosophy in his exploration for truths regarding the human condition.